OzVMX Forum

Clubroom => Competition => Topic started by: Nathan S on February 09, 2014, 04:14:24 pm

Title: Rule re-write.
Post by: Nathan S on February 09, 2014, 04:14:24 pm: For those with short attention spans, the 4th post in this thread (Reply #3) is the one you are looking for. This post, Post #2 and Post #5 are explainations of how and why.
Here's what I've come up with - I'm happy to have a civil discussion, happy to receive constructive input, happy to fix any mistakes (typos and otherwise),happy to change things.
Not so happy to listen to whinging... :)
At this stage, this is purely an exercise on OzVMX - but hopefully they will be a clear improvement and supported by the majority of punters, and can be published in the MA Manual.

Main goal of the re-write is to make the rules simpler and less ambigous. The problem areas in the current rules have been discussed ad nauseum, so I don't intend on going over it all again...
There is no intention to change the intent of the rules - everyone who has a legal bike under the current rules, should have a legal bike under the re-write.

Please read them all, and take some time to think before posting.
Please also have a close look at the current rules before complaining about an omission from the re-write. A lot of long standing rules have been removed or changed in recent years. The handlebar cross-bar pad thing surprised the hell out of me, for example...

OK, so there's the disclaimer over and done with - now let's look at what the current rules are (Sunday 9/2/14, 2pm):
MOMS: http://moms.org.au/
16a, CMX Nationals (Classic & Post Classic): http://moms.org.au/rules/18-classic-motocross-dirt-track/18-1-protective-clothing-classic-motocross-and-dirt-track/
16b, CMX Nationals classes: http://moms.org.au/rules/18-classic-motocross-dirt-track/18-2-eligibility/
16c, CMX Competition rules: http://moms.org.au/rules/18-classic-motocross-dirt-track/18-3-fuel-classic-mx-dirt-track/
16d, CMX Technical Regulations: http://moms.org.au/rules/18-classic-motocross-dirt-track/18-4-machine-and-class-identification-classic-mx-dirt-track/

16a defines Classic & Post-Classic, and the classes that are to be run at National Title meetings.
16b appears to be almost entirely redundant, and should simply disappear. Add clause 16.5 to the end of 16a, and delete the rest of 16b. I also believe that the age class races should be changed to "all eras up to and including Pre-78" for the Classic Nats, and "all eras up to and including pre-90" for the Post Classic Nats. But I am not trying to to change the rules, just clarify them.
16c is about standard requirements and procedures, like the need for scrutiny, numberplate colours, rider clothing, etc. MA-guff, in other words.
16d is about bike eligibility.

Most of the angst comes from 16d, so it deserves to be reproduced in full (NB: This is the current version, not the re-write!):

16.11 MACHINE ELIGIBILITY
16.11.1 Eligible Machines
16.11.1.1    Only machines conforming to the requirements set out in this chapter will be accepted for competition.
16.11.1.2    The onus of proof of eligibility shall rest wholly upon the rider or entrant of the machine. Service and parts manual publication dates are not proof of eligibility.
16.12 SOUND EMISSIONS
16.12.0.1    Sound testing must be carried out at all permitted events; however, it is not mandatory to test all machines.
16.12.1 Specifications
16.12.1.1    Sound emissions are set out in the table below:
30 metres (from side of track) ride by test
DISCIPLINE

LIMIT dB(A)
Dirt Track & Track (incl. Quads)    95
Record Attempts

No limit
16.12.2 Sound Control During Competition
16.12.2.1    The Sound Control Officer (SCO) must arrive in sufficient time for discussions with the Clerk of the Course and other Technical Officials in order that a suitable test site and testing policy can be agreed.
16.12.2.2    Machines can be tested before, or after competing in an event, chosen by ballot, or as required by a Steward, Clerk of Course or SCO.
16.12.2.3    Where government regulations or planning orders exist in relation to lower sound emissions or where a venue has lower sound emission requirements as part of the hire contract, the sound emission required will prevail over General Competition Rule 16.12.1.1.
16.12.3 Use of Sound Level Meters
16.12.3.1    Sound testing apparatus must:

Comply with international standard IEC 651, Type 1 or Type 2.
Include a compatible calibrator, which must be used immediately before testing begins and always just prior to a re-test if a disciplinary sanction may be imposed.

16.12.3.2    Sound testing apparatus must be set to:

‘Fast response’
‘A’ weighted,
Select range High 80~130 dB,
Activate the function MAX MIN – set on MAX,

16.12.3.3    ‘30 Metre ride by’ test

The sound levels will be measured with the sound meter/microphone fixed on a tripod, in the horizontal position, 30 metres from the edge of the track at a high speed point.

16.12.3.4    Tests shall not take place in the rain
16.12.4 Machine testing
16.12.4.1    If a machine fails, it can be represented for re-testing.
16.12.4.2    No person may compete in any event on a machine whose noise emissions exceed the prescribed levels.
16.12.4.3    A machine which does not comply with the sound limits can be presented several times.
16.13 FUEL
16.13.1 Fuel Warning
16.13.1.1    Fuels and lubricants are highly specialised substances and participants must be aware they may contain substances that are extremely dangerous to human health if misused, inhaled or allowed to contact skin.
16.13.1.2    Some of the components of fuel and lubricants are suspected of having the potential to cause cancer in rare circumstances.
16.13.1.3    The use of petrol as a general cleaning and washing agent is a common misuse of a potentially dangerous substance.
16.13.1.4    Fuels should be used and stored with extreme care and in accordance with the manufacturer’s instructions.
16.13.2 Fuel Testing
16.13.2.1    For any event, meeting or series, the relevant controlling body may direct that no fuels other than fuels of prescribed specifications and from a prescribed source may be used.

Tests to ensure that only prescribed fuels are used in an event, meeting or series may be administered at any time and place during the course of the same,
The Clerk of Course, Race Director or Chief Scrutineer may direct the administration of fuel tests.

16.13.2.2    Fuel tests must comply with the following procedures:

All containers for holding samples must be clean and constructed of robust non-reactive impermeable material, must be sealable, and must have provision for identification,
Equipment used for the extraction of fuel from machines must be clean and constructed of fuel non-reactive material,
All samples must be divided into two lots (Sample A and Sample B) of not less than 5ml each, which must be placed in separate containers,
Once samples are placed in containers, the containers must immediately be sealed and identified by reference to the machine from which the sample was taken. This information must be entered on a fuel sample certificate which must certify the date, place and time of taking the sample, the identity of the machine from which the sample was taken and the identity of the rider,
Both samples must remain in the control of the official who administered the test.
The rider or the representative must sign the fuel sample certificate acknowledging samples have been taken and are sealed,
All samples held by the official must be delivered as soon as practicable after the competition to the relevant controlling body which must deliver the Sample A as soon as practicable to a laboratory approved by MA where they must be tested for content and quality in accordance with standard scientific procedures,
The relevant controlling body must as soon as practicable after receipt of the results notify the rider or rider’s team representative and MA,
If the rider is dissatisfied with the test result of sample A, they may request sample B be tested at an MA approved laboratory in their presence.

16.13.3 Refuelling
16.13.3.1    During refuelling, each machine must be stationary with the engine stopped.
16.13.3.2    Refuelling will be deemed to have commenced when the fuel tank has been opened and completed when the tank is closed.
16.13.3.3    Smoking is strictly prohibited in areas where refuelling is permitted.
16.13.3.4    Riders are liable for exclusion from an event for failing to adhere to General Competition Rule 16.13.3.3, and are responsible for the actions of their mechanics and support team members.
16.13.4 Homologation of Fuel
16.13.4.1    Unleaded fuel produced by an oil company for sale in the Australian general transport fuel market through retail petrol pumps in at least five states does not have to be homologated. For the avoidance of doubt this means the fuel must be available for sale on demand from a roadside bowser outlet at each of at least five separate service stations in each of at least five Australian states or territories.
16.13.4.2    Organisations seeking homologation of fuel must provide MA with:

Two one-litre sealed containers of the fuel for analysis,
Details of the fuels characteristics,
The distribution network,
The price structure,
A homologation fee of $2,500 in the first year and $2,000 per year thereafter.

16.13.4.3    Fuels approved under this General Competition Rule will be published at www.ma.org.au.
16.13.5 Fuel: Classic Motocross and Classic Dirt Track
   Classic Motocross and Classic Dirt Track fuel used for competition must be:

ure methanol with no additives other than lubricating oil, or,
Unleaded fuel that is no more than 100 RON and meets rule 16.13.4.1,
Which contains no additives other than those added at the point of manufacture except for lubricating oil, or,
Be a brand of fuel homologated by MA that is compatible with the “Fuel Quality Standards Act 2000”, or,
Leaded fuel provided that the fuel is purchased from suppliers approved by Environmental Australia.

16.14 ENGINES: GENERAL
16.14.1 Reciprocating Engines
16.14.1.1    Cubic capacity = (D2 x 3.1416 x C x N)
4Where:
D = Bore in centimetres,
C = stroke in centimetres,
N = Number of cylinders.
16.14.2 Engine capacity tolerances
16.14.2.1    The actual engine capacity of a machine competing in a capacity class may not exceed the prescribed capacity for that class by more than 5%.
16.15 MACHINES AND COMPONENTS
16.15.1 Centre and Side Stands
16.15.1.1    Centre and side stands must be removed for all types of competition
16.15.2 Handlebars
16.15.2.1    The ends of the handlebars or twist grip sleeves must be securely plugged so as to present a flush or rounded end.
16.15.2.2    Handlebar levers must:

Have ball ends with a minimum diameter of:
15mm, for levers longer than 76mm,
10mm, for levers shorter than 76mm.
Measure no more than 200mm from the fulcrum to the extremity of the ball.

16.15.2.3    Throttle controls must be self-closing.
16.15.3 Kick Start Levers
16.15.3.1    Kick start levers, other than transverse, must be folding.
16.15.4 Drive Chain Protection
16.15.4.1    Primary drives (the drive connecting engine to clutch) must be guarded so as to prevent direct access to the chain or sprockets with the fingers.
16.15.4.2    The guard must be constructed of:

Metal having a minimum thickness of 1.6mm, which may be mesh or expanded metal provided the openings do not exceed 10mm, or
Fibreglass having a minimum thickness of 3mm.

16.15.4.3    If a plastic, fibreglass or part open chain guard is used, a steel bolt of not less than 10mm diameter, placed outside the bottom rear quadrant of the clutch sprocket. This bolt, if damaged, must be replaced.
16.15.4.4    Projecting sprockets, which are not behind a clutch assembly or directly behind a frame member, must be guarded where the sprocket teeth are further than 30mm from a frame member or swinging arm.
16.15.4.5    A counter shaft sprocket which is more than 30mm from the outside of the swing arm pivot must be covered.
16.15.4.6    Other than CMX/CDT A chain guard made of suitable material must be fitted in a way to prevent trapping between the lower drive chain run and the final drive sprocket at the rear wheel.
16.15.5 Tyres
16.15.5.1    Tyres must comply with the following:

Metal studs, spikes, chain, rope or other non-skid attachments may not be used unless permitted by the relevant Supplementary Regulations.
Paddle or scoop treaded tyres may not be fitted.

16.15.5.2    Valve caps must be used for all competitions.
16.15.6 Mudguards
16.15.6.1    Either a rear mudguard or a seat must be fitted which extends at least 20 degrees to the rear of a vertical line drawn through the rear wheel axle.
16.15.6.2    Mudguards must be made of a material, which is not liable to cause personal injury if deformed.
16.15.7 Acceptable machines and components: Pre 60 Solo
16.15.7.1    Acceptable for the pre 60 class are machines and components built up to and including the 1959 model. The only exception to this General Competition Rule is where the model remains unaltered after this date.
16.15.7.2    Frames of any manufacture are acceptable within the suspension criteria and considerate of the era.
16.15.7.3    Front wheel travel will not exceed 178mm (7 inches) rear wheel travel will be limited to 102mm (4 inches) measured at the axle. Rear shock absorbers will be in the original position using the original mounting points.
16.15.7.4    Plastic and fibreglass is not permitted.
16.15.7.5    Engines and gearboxes must remain externally unchanged.
16.15.7.6    Period carburettors or Amal Mk1 Concentric.
16.15.7.7    Exhaust may be modified but must follow the original lines and meet sound control regulations in GCR 16.12.
16.15.7.8    Folding footrests must be fitted.
16.15.7.9    Countershaft sprocket covers will be fitted.
16.15.8 Acceptable machines and components: Pre 65 Solo
16.15.8.1    Acceptable for the pre 65 class are machines and components built up to and including the 1964 model. The only exception to this rule is where the model remains unaltered after this date.
16.15.8.2    Frames of any manufacture are acceptable within the suspension criteria and considerate of the era.
16.15.8.3    Front wheel travel will not exceed 178mm (7 inches) rear wheel travel will be limited to 102mm (4 inches) measured at the axle.
16.15.8.4    Rear shock absorbers will be in the original position using the original mounting points.
16.15.8.5    Engines and gearboxes must remain externally unchanged.
16.15.8.6    Carburettors of any type pre 75 round slide may be used.
16.15.8.7    Exhaust may be modified but must follow the original lines and meet sound control regulations in GCR 16.12.
16.15.8.8    Folding footrests must be fitted.
16.15.8.9    Countershaft sprocket covers will be fitted.
16.15.9 Acceptable machines and components: Pre 70 Solo
16.15.9.1    Acceptable for the pre 70 class are machines and components built up to and including the 1969 model. The only exception to this rule is where the model remains unaltered after this date.
16.15.9.2    Front wheel travel will not exceed 178mm (7 inches) rear wheel travel will be limited to 102mm (4 inches) measured at the axle. Rear shock absorbers will be in the original position using the original mounting points.
16.15.9.3    Engines and gearboxes must remain externally unchanged.
16.15.9.4    Carburettors; any type of pre 75 round slide may be used.
16.15.9.5    No reed valves permitted.
16.15.9.6    Exhaust may be modified but must follow the original lines and meet sound control regulations in GCR 16.12.
16.15.9.7    Folding footrests must be fitted.
16.15.9.8    Countershaft sprocket covers will be fitted.
16.15.9.9    Yamaha XS1 and XS650 engines are eligible.
16.15.9.10    Acceptable follow on models pre 70

AJS Stormer 250,
Greeves griffon models,
Yamaha AT1, DT1, CT1, RT1 pre reed block.

16.15.10 Acceptable machines and components: Pre 75 Solo
16.15.10.1    Acceptable for the pre 75 class are machines and components built up to and including the 1974 model. The only exception to this rule is where the model remains unaltered after this date.
16.15.10.2    Front wheel travel will not exceed 178mm (7 inches) rear wheel travel will be limited to 102mm (4 inches) measured at the axle. Rear shock absorbers will be in the original position using the original mounting points.
16.15.10.3    Engines and gearboxes must remain externally unchanged.
16.15.10.4    Carburettors; any type of pre 75 round slide may be used.
16.15.10.5    XS1 and XS650 engines are eligible.
16.15.10.6    Exhaust may be modified but must follow the original lines and meet sound control regulations in GCR 16.12.
16.15.10.7    Folding footrests must be fitted.
16.15.10.8    Countershaft sprocket covers will be fitted.
16.15.10.9    Acceptable follow on models pre 75

Honda CR125M1, XL250K1, XL350K1, MT250 and MT125
Yamaha YZ360B, DT250B,
Suzuki TS400 (all).

16.15.11 Acceptable machines and components: Pre 78 Solo
16.15.11.1    Acceptable for the pre 78 classes:
a) Machines and components that are limited to the 1975, 1976, 1977 models alone. The only exception to this rule is where the model remains unaltered after this date.
b) Pre 78 Women’s class: acceptable machines and components are up to and including the 1977 model year. The only exception to this rule is where the model remains unaltered after this date.
16.15.11.2    Front wheel travel will not exceed 229mm (9 inches) rear wheel travel will be limited to 229mm (9 inches) measured at the axle. Rear shock absorbers will be in the original position using the original mounting points.
16.15.11.3    Engines and gearboxes must remain externally unchanged.
16.15.11.4    Carburettors; any type of pre 78 round slide may be used.
16.15.11.5    Exhaust may be modified but must follow the original lines and meet sound control regulations in GCR 16.12.
16.15.11.6    Folding footrests must be fitted.
16.15.11.7    Countershaft sprocket covers will be fitted.
16.15.11.8    Acceptable follow on models pre 78

CZ 125 1978, CZ400 1978,
Montesa VB (must comply to suspension limits),
Yamaha TT500 1978.

16.15.12 Acceptable machines and components: Evolution Class Solo
16.15.12.1    Bikes will be OEM (original equipment manufacturer).
16.15.12.2    Modifications converting later equipment to comply will not be allowed.
16.15.12.3    All components will be of the period the machine was manufactured:

No linkage suspension,
No disk brakes,
Air cooled motors.

16.15.12.4    Carburettors; period flat slide carburettors and any round slide carburettor may be used.
16.15.12.5    Engines and gearboxes must remain externally unchanged.
16.15.12.6    Exhaust may be modified but must follow the original lines and be fitted with an effective muffler.
16.15.12.7    Folding footrests must be fitted.
16.15.12.8    Countershaft sprocket covers will be fitted.
16.15.12.9    The handlebars must be equipped with a protection pad on the cross bar. Handlebars not fitted with a cross bar must be equipped with a protection pad located in the middle of the handlebars covering the handlebar clamps.
16.15.13 Acceptable machines and components: Pre 85 Solo
16.15.13.1    Acceptable for the pre 85 class are machines and components built up to and including the 1984 model. The only exception to this rule is where the model remains unaltered after this date.
16.15.13.2    Carburettors; period flat slide carburettors and any round slide carburettor may be used.
16.15.13.3    Engines and gearboxes must remain externally unchanged.
16.15.13.4    Exhaust may be modified but must follow the original lines and be fitted with an effective muffler.
16.15.13.5    Folding footrests must be fitted.
16.15.13.6    Countershaft sprocket covers will be fitted.
16.15.13.7    The handlebars must be equipped with a protection pad on the cross bar. Handlebars not fitted with a cross bar must be equipped with a protection pad located in the middle of the handlebars covering the handlebar clamps.
16.15.14 Acceptable machines and components: Pre 90 Solo
16.15.14.1    Acceptable for the pre 90 class are machines and components built up to and including the 1989 model. The only exception to this rule is where the model remains unaltered after this date.
16.15.14.2    Carburettors; period flat slide carburettors and any round slide carburettor may be used.
16.15.14.3    Engines and gearboxes must remain externally unchanged.
16.15.14.4    Exhaust may be modified but must follow the original lines and be fitted with an effective muffler.
16.15.14.5    Folding footrests must be fitted.
16.15.14.6    Countershaft sprocket covers will be fitted.
16.15.14.7    The handlebars must be equipped with a protection pad on the cross bar. Handlebars not fitted with a cross bar must be equipped with a protection pad located in the middle of the handlebars covering the handlebar clamps.
16.16 SLIDERS
16.16.1 Slider Frames
16.16.1.1    The frame must:

Have a conventional swing arm rear suspension with twin shock absorbers,
Have a front wheel diameter of 23”,
Have a rear wheel diameter of 19”,
Have rear tyres with a maximum tread pattern depth of 8mm,
Not be fitted with leading-link front forks.

16.16.2 Slider Solo Engines
16.16.2.1    The slider engine must:

Be a single cylinder,
When four stroke be 2- valve push rod operation,
Have a single spark plug,
Be vertical in the chassis,
Be fitted with a round slide carburettor, or
Be a period two stroke compatible with class entered.

16.16.3 Slider Gearbox: Classic Long Track
16.16.3.1    The gearbox must have at least two gears.
16.16.4 Slider Sidecar Frames
16.16.4.1    Conventional type frames as used prior to 31st December 1976 must be used.
16.16.5 Slider Sidecar Engines
16.16.5.1    Engines must have been manufactured before 31st December 1976.
16.17 SIDECARS
16.17.1 All Classes
16.17.1.1    Left -hand and right -hand sidecars may compete against each other in Classic Motocross.
16.17.2 Frames and Parts
16.17.2.1    For the Pre-1975 classes, all performance parts except frames must be manufactured before 31st December 1974 and must comply with the following:

Wheel track measurement, taken between the longitudinal centres of the rear and sidecar wheels must be between 810mm and 1100mm,
The minimum ground clearance must be 175mm unladen,
The maximum lean of the motorcycle at saddle height mustbe 50mm,
The dimensions of the sidecar baseboard in plain view, taken from a line drawn no further rearwards than the lowest point of the front down-tube to the forward most point of the sidecar wheel tyre and terminating no further rearwards than a line drawn at right angles to the machine from the rearmost point of the rear tyre, must be:
At least 760mm long adjacent to the sidecar wheel,
At least 300mm wide with at least 25mm radius to all corners.
There must be no more than 50mm between baseboard and motorcycle and between baseboard and sidecar wheel. The baseboard must be arranged so as not to allow the passenger’s feet to be trapped,
There must be no less than 4 sidecar attachment points,
Stirrup fitting for the passenger’s feet are not permitted,
Handholds:
Must be finished with a loop of at least 100mm,
Must not project beyond a line taken with the outer edge of the sidecar mudguard or bodywork,
Adjacent to the nose section of the sidecar and less than 200mm from the track surface must be at an angle of at least 45° from the horizontal.
The rear end of the rear wheel mudguard must terminate not more than 65° above a horizontal line drawn through the rear wheel axle and be valanced to baseboard level on the inside,
The sidecar mudguard must cover at least 135° of the periphery of the wheel and be valanced to baseboard level on the inside,
No machine may be fitted with scoop or paddle tyres,
Suspension travel must not exceed:
152mm (6”) 178mm (7”) measured at the front axle,
102mm (4”) at the rear axle.
Rear tyre width must not exceed 135mm (5.3”),
Brakes:
Front – single caliper, single disc may be fitted provided they were manufactured before 31st December 1974,
Rear – rear disc brakes may be used provided they were fitted as standard equipment for that particular combination.

Only round-slide carburettors manufactured within the relevant period may be used,
Engine capacity must be up to 1300cc.

16.17.2.2    Pre-1985 is for sidecars constructed with motors manufactured before 31st December 1984.
16.17.2.3    A lanyard operated ignition cut-out switch, operating on the primary circuit, must be fitted to the following with a maximum length of one metre:
DISCIPLINE

MACHINE
Motocross    Sidecars
Dirt track    Sidecars
16.17.2.4    Pre-1968 will be for sidecars constructed from road going frames and all major components are those commercially available within the period.
16.17.2.5    The following table sets out the machines and components which eligibility scrutineers may use as a guide in determining eligibility. Entrants must prove eligibility of machines not listed below.
MAKE

MODEL(S)
Wasp    All up to and including RT2, RT8 and RT14
Hagon    All up to 31st December 1974
Yamaha    XS 650 all models
Honda    Any K series
Norton    All 750, 850 to Mk2 only
Westlake    All up to 850cc and 31st December 1974
Triumph    All up to T150
CCM    All BSA B50 based models
Title: Re: Rule re-write.
Post by: Ted on February 09, 2014, 04:19:46 pm: Is it any wonder Vinduros have become so popular 8)
Title: Re: Rule re-write.
Post by: Nathan S on February 09, 2014, 04:24:29 pm: Indeed, Ted...

--------------------

So... here's the first part of what I propose:

16.12, 16.13, 16.14, 16.15 up to and including 16.15.5 are all moved to section 16c. They are important (to MA...) but having them in with the specific CMX machine requirements just confuses the issue.

16.15.4.6 is simply deleted - there's no point in having a rule that instantly disqualifies itself.

So far, there's been a change to formatting and removed one rule that does nothing (16.15.4.6) - no other changes.
The rules we now have look like this:

---------------------------------

16.11 MACHINE ELIGIBILITY
16.11.1 Eligible Machines
16.11.1.1    Only machines conforming to the requirements set out in this chapter will be accepted for competition.
16.11.1.2    The onus of proof of eligibility shall rest wholly upon the rider or entrant of the machine. Service and parts manual publication dates are not proof of eligibility.

16.15.7 Acceptable machines and components: Pre 60 Solo
16.15.7.1    Acceptable for the pre 60 class are machines and components built up to and including the 1959 model. The only exception to this General Competition Rule is where the model remains unaltered after this date.
16.15.7.2    Frames of any manufacture are acceptable within the suspension criteria and considerate of the era.
16.15.7.3    Front wheel travel will not exceed 178mm (7 inches) rear wheel travel will be limited to 102mm (4 inches) measured at the axle. Rear shock absorbers will be in the original position using the original mounting points.
16.15.7.4    Plastic and fibreglass is not permitted.
16.15.7.5    Engines and gearboxes must remain externally unchanged.
16.15.7.6    Period carburettors or Amal Mk1 Concentric.
16.15.7.7    Exhaust may be modified but must follow the original lines and meet sound control regulations in GCR 16.12.
16.15.7.8    Folding footrests must be fitted.
16.15.7.9    Countershaft sprocket covers will be fitted.
16.15.8 Acceptable machines and components: Pre 65 Solo
16.15.8.1    Acceptable for the pre 65 class are machines and components built up to and including the 1964 model. The only exception to this rule is where the model remains unaltered after this date.
16.15.8.2    Frames of any manufacture are acceptable within the suspension criteria and considerate of the era.
16.15.8.3    Front wheel travel will not exceed 178mm (7 inches) rear wheel travel will be limited to 102mm (4 inches) measured at the axle.
16.15.8.4    Rear shock absorbers will be in the original position using the original mounting points.
16.15.8.5    Engines and gearboxes must remain externally unchanged.
16.15.8.6    Carburettors of any type pre 75 round slide may be used.
16.15.8.7    Exhaust may be modified but must follow the original lines and meet sound control regulations in GCR 16.12.
16.15.8.8    Folding footrests must be fitted.
16.15.8.9    Countershaft sprocket covers will be fitted.
16.15.9 Acceptable machines and components: Pre 70 Solo
16.15.9.1    Acceptable for the pre 70 class are machines and components built up to and including the 1969 model. The only exception to this rule is where the model remains unaltered after this date.
16.15.9.2    Front wheel travel will not exceed 178mm (7 inches) rear wheel travel will be limited to 102mm (4 inches) measured at the axle. Rear shock absorbers will be in the original position using the original mounting points.
16.15.9.3    Engines and gearboxes must remain externally unchanged.
16.15.9.4    Carburettors; any type of pre 75 round slide may be used.
16.15.9.5    No reed valves permitted.
16.15.9.6    Exhaust may be modified but must follow the original lines and meet sound control regulations in GCR 16.12.
16.15.9.7    Folding footrests must be fitted.
16.15.9.8    Countershaft sprocket covers will be fitted.
16.15.9.9    Yamaha XS1 and XS650 engines are eligible.
16.15.9.10    Acceptable follow on models pre 70

AJS Stormer 250,
Greeves griffon models,
Yamaha AT1, DT1, CT1, RT1 pre reed block.

16.15.10 Acceptable machines and components: Pre 75 Solo
16.15.10.1    Acceptable for the pre 75 class are machines and components built up to and including the 1974 model. The only exception to this rule is where the model remains unaltered after this date.
16.15.10.2    Front wheel travel will not exceed 178mm (7 inches) rear wheel travel will be limited to 102mm (4 inches) measured at the axle. Rear shock absorbers will be in the original position using the original mounting points.
16.15.10.3    Engines and gearboxes must remain externally unchanged.
16.15.10.4    Carburettors; any type of pre 75 round slide may be used.
16.15.10.5    XS1 and XS650 engines are eligible.
16.15.10.6    Exhaust may be modified but must follow the original lines and meet sound control regulations in GCR 16.12.
16.15.10.7    Folding footrests must be fitted.
16.15.10.8    Countershaft sprocket covers will be fitted.
16.15.10.9    Acceptable follow on models pre 75

Honda CR125M1, XL250K1, XL350K1, MT250 and MT125
Yamaha YZ360B, DT250B,
Suzuki TS400 (all).

16.15.11 Acceptable machines and components: Pre 78 Solo
16.15.11.1    Acceptable for the pre 78 classes:
a) Machines and components that are limited to the 1975, 1976, 1977 models alone. The only exception to this rule is where the model remains unaltered after this date.
b) Pre 78 Women’s class: acceptable machines and components are up to and including the 1977 model year. The only exception to this rule is where the model remains unaltered after this date.
16.15.11.2    Front wheel travel will not exceed 229mm (9 inches) rear wheel travel will be limited to 229mm (9 inches) measured at the axle. Rear shock absorbers will be in the original position using the original mounting points.
16.15.11.3    Engines and gearboxes must remain externally unchanged.
16.15.11.4    Carburettors; any type of pre 78 round slide may be used.
16.15.11.5    Exhaust may be modified but must follow the original lines and meet sound control regulations in GCR 16.12.
16.15.11.6    Folding footrests must be fitted.
16.15.11.7    Countershaft sprocket covers will be fitted.
16.15.11.8    Acceptable follow on models pre 78

CZ 125 1978, CZ400 1978,
Montesa VB (must comply to suspension limits),
Yamaha TT500 1978.

16.15.12 Acceptable machines and components: Evolution Class Solo
16.15.12.1    Bikes will be OEM (original equipment manufacturer).
16.15.12.2    Modifications converting later equipment to comply will not be allowed.
16.15.12.3    All components will be of the period the machine was manufactured:

No linkage suspension,
No disk brakes,
Air cooled motors.

16.15.12.4    Carburettors; period flat slide carburettors and any round slide carburettor may be used.
16.15.12.5    Engines and gearboxes must remain externally unchanged.
16.15.12.6    Exhaust may be modified but must follow the original lines and be fitted with an effective muffler.
16.15.12.7    Folding footrests must be fitted.
16.15.12.8    Countershaft sprocket covers will be fitted.
16.15.12.9    The handlebars must be equipped with a protection pad on the cross bar. Handlebars not fitted with a cross bar must be equipped with a protection pad located in the middle of the handlebars covering the handlebar clamps.
16.15.13 Acceptable machines and components: Pre 85 Solo
16.15.13.1    Acceptable for the pre 85 class are machines and components built up to and including the 1984 model. The only exception to this rule is where the model remains unaltered after this date.
16.15.13.2    Carburettors; period flat slide carburettors and any round slide carburettor may be used.
16.15.13.3    Engines and gearboxes must remain externally unchanged.
16.15.13.4    Exhaust may be modified but must follow the original lines and be fitted with an effective muffler.
16.15.13.5    Folding footrests must be fitted.
16.15.13.6    Countershaft sprocket covers will be fitted.
16.15.13.7    The handlebars must be equipped with a protection pad on the cross bar. Handlebars not fitted with a cross bar must be equipped with a protection pad located in the middle of the handlebars covering the handlebar clamps.
16.15.14 Acceptable machines and components: Pre 90 Solo
16.15.14.1    Acceptable for the pre 90 class are machines and components built up to and including the 1989 model. The only exception to this rule is where the model remains unaltered after this date.
16.15.14.2    Carburettors; period flat slide carburettors and any round slide carburettor may be used.
16.15.14.3    Engines and gearboxes must remain externally unchanged.
16.15.14.4    Exhaust may be modified but must follow the original lines and be fitted with an effective muffler.
16.15.14.5    Folding footrests must be fitted.
16.15.14.6    Countershaft sprocket covers will be fitted.
16.15.14.7    The handlebars must be equipped with a protection pad on the cross bar. Handlebars not fitted with a cross bar must be equipped with a protection pad located in the middle of the handlebars covering the handlebar clamps.
16.16 SLIDERS
16.16.1 Slider Frames
16.16.1.1    The frame must:

Have a conventional swing arm rear suspension with twin shock absorbers,
Have a front wheel diameter of 23”,
Have a rear wheel diameter of 19”,
Have rear tyres with a maximum tread pattern depth of 8mm,
Not be fitted with leading-link front forks.

16.16.2 Slider Solo Engines
16.16.2.1    The slider engine must:

Be a single cylinder,
When four stroke be 2- valve push rod operation,
Have a single spark plug,
Be vertical in the chassis,
Be fitted with a round slide carburettor, or
Be a period two stroke compatible with class entered.

16.16.3 Slider Gearbox: Classic Long Track
16.16.3.1    The gearbox must have at least two gears.
16.16.4 Slider Sidecar Frames
16.16.4.1    Conventional type frames as used prior to 31st December 1976 must be used.
16.16.5 Slider Sidecar Engines
16.16.5.1    Engines must have been manufactured before 31st December 1976.
16.17 SIDECARS
16.17.1 All Classes
16.17.1.1    Left -hand and right -hand sidecars may compete against each other in Classic Motocross.
16.17.2 Frames and Parts
16.17.2.1    For the Pre-1975 classes, all performance parts except frames must be manufactured before 31st December 1974 and must comply with the following:

Wheel track measurement, taken between the longitudinal centres of the rear and sidecar wheels must be between 810mm and 1100mm,
The minimum ground clearance must be 175mm unladen,
The maximum lean of the motorcycle at saddle height mustbe 50mm,
The dimensions of the sidecar baseboard in plain view, taken from a line drawn no further rearwards than the lowest point of the front down-tube to the forward most point of the sidecar wheel tyre and terminating no further rearwards than a line drawn at right angles to the machine from the rearmost point of the rear tyre, must be:
At least 760mm long adjacent to the sidecar wheel,
At least 300mm wide with at least 25mm radius to all corners.
There must be no more than 50mm between baseboard and motorcycle and between baseboard and sidecar wheel. The baseboard must be arranged so as not to allow the passenger’s feet to be trapped,
There must be no less than 4 sidecar attachment points,
Stirrup fitting for the passenger’s feet are not permitted,
Handholds:
Must be finished with a loop of at least 100mm,
Must not project beyond a line taken with the outer edge of the sidecar mudguard or bodywork,
Adjacent to the nose section of the sidecar and less than 200mm from the track surface must be at an angle of at least 45° from the horizontal.
The rear end of the rear wheel mudguard must terminate not more than 65° above a horizontal line drawn through the rear wheel axle and be valanced to baseboard level on the inside,
The sidecar mudguard must cover at least 135° of the periphery of the wheel and be valanced to baseboard level on the inside,
No machine may be fitted with scoop or paddle tyres,
Suspension travel must not exceed:
152mm (6”) 178mm (7”) measured at the front axle,
102mm (4”) at the rear axle.
Rear tyre width must not exceed 135mm (5.3”),
Brakes:
Front – single caliper, single disc may be fitted provided they were manufactured before 31st December 1974,
Rear – rear disc brakes may be used provided they were fitted as standard equipment for that particular combination.

Only round-slide carburettors manufactured within the relevant period may be used,
Engine capacity must be up to 1300cc.

16.17.2.2    Pre-1985 is for sidecars constructed with motors manufactured before 31st December 1984.
16.17.2.3    A lanyard operated ignition cut-out switch, operating on the primary circuit, must be fitted to the following with a maximum length of one metre:
DISCIPLINE

MACHINE
Motocross    Sidecars
Dirt track    Sidecars
16.17.2.4    Pre-1968 will be for sidecars constructed from road going frames and all major components are those commercially available within the period.
16.17.2.5    The following table sets out the machines and components which eligibility scrutineers may use as a guide in determining eligibility. Entrants must prove eligibility of machines not listed below.
MAKE

MODEL(S)
Wasp    All up to and including RT2, RT8 and RT14
Hagon    All up to 31st December 1974
Yamaha    XS 650 all models
Honda    Any K series
Norton    All 750, 850 to Mk2 only
Westlake    All up to 850cc and 31st December 1974
Triumph    All up to T150
CCM    All BSA B50 based models
Title: Re: Rule re-write.
Post by: Nathan S on February 09, 2014, 04:25:38 pm: And then, finally, we get to the re-write!
I've ADDED quite a bit of stuff, but the word count is still substantially less than it was (not including the MA guff that I sent off to 16c) - so I've had a win on that bit, at least...

---------------------------------------------------------

16.11 MACHINE ELIGIBILITY
16.11.1 Eligible Machines
16.11.1.1    Only machines conforming to the requirements set out in chapter 16 will be accepted for competition.
16.11.1.2    The onus of proof of eligibility shall rest wholly upon the rider or entrant of the machine. Service and parts manual publication dates are not proof of eligibility.

16.15.7 Acceptable machines and components:
All Eras:
a) Major Components are: Frame, swing arm, forks, wheel hubs, triple clamps, engine cases, cylinder(s), and cylinder head(s). A machine's era will be defined by its newest major component.
b) Any major component that is visually similar and operationally indistinguishable from the original will be accepted regardless of the date of manufacture.
ba) Any major component that is visually similar and operationally indistinguishable from aftermarket components available in the era, will be accepted regardless of the date of manufacture.
c) Any modifications to major components must be using principles and techniques that were available in the era the machine is entered in.
d) Rear shock absorbers will be in the original position(s), using the original mounting points.
da) Folding footrests must be fitted.

Pre 60 Solo. This class is intended to represent the formative era of motocross.
16.15.7.1    The pre 60 class is for machines that closely represent those built up to (and including) 1959 models.
16.15.7.3    Front wheel travel will not exceed 178mm (7 inches) rear wheel travel will be limited to 102mm (4 inches) measured at the axle.
16.15.7.4    Plastic and fibreglass is not permitted.
16.15.7.6    Period carburettors or Amal Mk1 Concentric.
16.15.7.7 Reed valves are not permitted.

Pre 65 Solo. This class is intended to represent the first generation of purpose-built motocross bikes.
16.15.8.1    The pre 65 class is for machines that closely represent those that were built up to (and including) 1964 models.
16.15.8.3    Front wheel travel will not exceed 178mm (7 inches) rear wheel travel will be limited to 102mm (4 inches) measured at the axle.
16.15.8.6    Carburettors of any type pre 75 round slide may be used.
16.15.8.7 Reed valves are not permitted.

Pre 70. This class is intended to represent the era where 2-stroke machines became dominant.
16.15.9.1     The pre 70 class is for machines that closely represent those built up to (and including) 1969 models.
16.15.9.2     Front wheel travel will not exceed 178mm (7 inches) rear wheel travel will be limited to 102mm (4 inches) measured at the axle.
16.15.9.4     Carburettors; any type of pre 75 round slide may be used.
16.15.9.5     Reed valves are not permitted.
16.15.9.9    Yamaha XS1 and XS650 engines are eligible.
16.15.9.10    Acceptable follow on models: AJS Stormer 250; Greeves griffon models; Yamaha AT1, DT1, CT1, RT1 pre reed block.

Pre 75 Solo. This class is intended to represent the end of the short travel suspension era.
16.15.10.1    The pre 75 class is for machines that closely represent those built up to (and including) 1974 models.
16.15.10.2    Front wheel travel will not exceed 178mm (7 inches) rear wheel travel will be limited to 102mm (4 inches) measured at the axle.
16.15.10.4    Carburettors; any type of pre 75 round slide may be used.
16.15.10.5    XS1 and XS650 engines are eligible.
16.15.10.9    Acceptable follow on models pre 75:
Honda CR125M1, XL250K1, XL350K1, MT250 (all) and MT125 (all)
Yamaha YZ360B, DT250B,
Suzuki TS400 (all).

Pre 78 Solo and Women's Pre-78. This class is intended to represent the transition era between the short travel Pre-75 machines and the long travel Evo machines.
16.15.11.1    The pre 78 class is for machines that closely represent those built up to (and including) 1977 models.
16.15.11.2    Front wheel travel will not exceed 229mm (9 inches) rear wheel travel will be limited to 229mm (9 inches) measured at the axle.
16.15.11.4    Carburettors; any type of pre 78 round slide may be used.
16.15.11.8    Acceptable follow on models pre 78

CZ 125 1978, CZ400 1978,
Montesa VB (must comply to suspension limits),
Yamaha TT500 1978.

Evolution. This class is intended to represent the era of long suspension travel, before water-cooling, disc brakes and linkage rear suspension became dominant.
16.15.12.1    The Evo class is for machines that use drum brakes, air-cooling and non-linkage rear suspension, as was commonplace until 1981. It also allows for later machines up to (and including) 1985 models that retained this technology.
e) Evolution class bikes must have Non-linkage rear suspension, No disc brakes, and Air cooled motors.
16.15.12.4    Carburettors; period flat slide carburettors and any round slide carburettor may be used.
16.15.12.9    The handlebars must be equipped with a protection pad on the cross bar. Handlebars not fitted with a cross bar must be equipped with a protection pad located in the middle of the handlebars covering the handlebar clamps.

Pre 85 Solo. This class is intended to represent the era of the first generation of disc front brakes, water cooling, linkage rear suspension and exhaust power valves.
16.15.13.1    The pre 85 class is for machines that closely represent those built up to (and including) 1984 models.
16.15.13.2     Carburettors; pre-85 flat slide carburettors and any round slide carburettor may be used.
16.15.13.7    The handlebars must be equipped with a protection pad on the cross bar. Handlebars not fitted with a cross bar must be equipped with a protection pad located in the middle of the handlebars covering the handlebar clamps.

Pre 90 Solo. This class is intended to represent the era where rear disc brakes, upside down forks, and the second generation of exhaust power valves became common place.
16.15.14.1    The pre 90 class is for machines that closely represent those built up to (and including) 1989 models.
16.15.14.2    Carburettors; period flat slide carburettors and any round slide carburettor may be used.
16.15.14.7    The handlebars must be equipped with a protection pad on the cross bar. Handlebars not fitted with a cross bar must be equipped with a protection pad located in the middle of the handlebars covering the handlebar clamps.

16.16 SLIDERS
16.16.1 Slider Frames
16.16.1.1    The frame must:

Have a conventional swing arm rear suspension with twin shock absorbers,
Have a front wheel diameter of 23”,
Have a rear wheel diameter of 19”,
Have rear tyres with a maximum tread pattern depth of 8mm,
Not be fitted with leading-link front forks.

16.16.2 Slider Solo Engines
16.16.2.1    The slider engine must:

Be a single cylinder,
When four stroke be 2- valve push rod operation,
Have a single spark plug,
Be vertical in the chassis,
Be fitted with a round slide carburettor, or
Be a period two stroke compatible with class entered.

16.16.3 Slider Gearbox: Classic Long Track
16.16.3.1    The gearbox must have at least two gears.
16.16.4 Slider Sidecar Frames
16.16.4.1    Conventional type frames as used prior to 31st December 1976 must be used.
16.16.5 Slider Sidecar Engines
16.16.5.1    Engines must have been manufactured before 31st December 1976.
16.17 SIDECARS
16.17.1 All Classes
16.17.1.1    Left -hand and right -hand sidecars may compete against each other in Classic Motocross.
16.17.2 Frames and Parts
16.17.2.1    For the Pre-1975 classes, all performance parts except frames must be manufactured before 31st December 1974 and must comply with the following:

Wheel track measurement, taken between the longitudinal centres of the rear and sidecar wheels must be between 810mm and 1100mm,
The minimum ground clearance must be 175mm unladen,
The maximum lean of the motorcycle at saddle height mustbe 50mm,
The dimensions of the sidecar baseboard in plain view, taken from a line drawn no further rearwards than the lowest point of the front down-tube to the forward most point of the sidecar wheel tyre and terminating no further rearwards than a line drawn at right angles to the machine from the rearmost point of the rear tyre, must be:
At least 760mm long adjacent to the sidecar wheel,
At least 300mm wide with at least 25mm radius to all corners.
There must be no more than 50mm between baseboard and motorcycle and between baseboard and sidecar wheel. The baseboard must be arranged so as not to allow the passenger’s feet to be trapped,
There must be no less than 4 sidecar attachment points,
Stirrup fitting for the passenger’s feet are not permitted,
Handholds:
Must be finished with a loop of at least 100mm,
Must not project beyond a line taken with the outer edge of the sidecar mudguard or bodywork,
Adjacent to the nose section of the sidecar and less than 200mm from the track surface must be at an angle of at least 45° from the horizontal.
The rear end of the rear wheel mudguard must terminate not more than 65° above a horizontal line drawn through the rear wheel axle and be valanced to baseboard level on the inside,
The sidecar mudguard must cover at least 135° of the periphery of the wheel and be valanced to baseboard level on the inside,
No machine may be fitted with scoop or paddle tyres,
Suspension travel must not exceed:
152mm (6”) 178mm (7”) measured at the front axle,
102mm (4”) at the rear axle.
Rear tyre width must not exceed 135mm (5.3”),
Brakes:
Front – single caliper, single disc may be fitted provided they were manufactured before 31st December 1974,
Rear – rear disc brakes may be used provided they were fitted as standard equipment for that particular combination.

Only round-slide carburettors manufactured within the relevant period may be used,
Engine capacity must be up to 1300cc.

16.17.2.2    Pre-1985 is for sidecars constructed with motors manufactured before 31st December 1984.
16.17.2.3    A lanyard operated ignition cut-out switch, operating on the primary circuit, must be fitted to the following with a maximum length of one metre:
DISCIPLINE

MACHINE
Motocross    Sidecars
Dirt track    Sidecars
16.17.2.4    Pre-1968 will be for sidecars constructed from road going frames and all major components are those commercially available within the period.
16.17.2.5    The following table sets out the machines and components which eligibility scrutineers may use as a guide in determining eligibility. Entrants must prove eligibility of machines not listed below.
MAKE

MODEL(S)
Wasp    All up to and including RT2, RT8 and RT14
Hagon    All up to 31st December 1974
Yamaha    XS 650 all models
Honda    Any K series
Norton    All 750, 850 to Mk2 only
Westlake    All up to 850cc and 31st December 1974
Triumph    All up to T150
CCM    All BSA B50 based models
Title: Re: Rule re-write.
Post by: Nathan S on February 09, 2014, 04:28:31 pm: Now that lots of people's brains have exploded, here's the same rules with annotations in blue. (The blue bits aren't part of the rules - they help people understand the changes).

16.11 MACHINE ELIGIBILITY
16.11.1 Eligible Machines
16.11.1.1    Only machines conforming to the requirements set out in chapter 16 will be accepted for competition.
16.11.1.2    The onus of proof of eligibility shall rest wholly upon the rider or entrant of the machine. Service and parts manual publication dates are not proof of eligibility.

16.15.7 Acceptable machines and components:
All Eras: (this saves repeating a whole lot of stuff for every category)
a) Major Components are: Frame, swing arm, forks, wheel hubs, triple clamps, engine cases, cylinder(s), and cylinder head(s). A machine's era will be defined by its newest major component. (defining the major components is important - it makes the difference between "do I need to use old tyres?" and "can I fit the forks off my 2005 Honda?")
b) Any major component that is visually similar and operationally indistinguishable from the original will be accepted regardless of the date of manufacture. (I am not happy with "similar" - the word "identical" is too strict for minor differences like casting changes, but "similar" is too vague. Open to input on that one!
This bit also replaces the need to specifically allow identical carry-over models)
ba) Any major component that is visually similar and operationally indistinguishable from aftermarket components available in the era, will be accepted regardless of the date of manufacture. (As above)
c) Any modifications to major components must be using principles and techniques that were available in the era the machine is entered in. (just stops loop-holing tactics)
d) Rear shock absorbers will be in the original position(s), using the original mounting points. (As well as avoiding repeating the same thing over and over again, this kills the "single-shock to twin-shock Evo" bike argument dead)
da) Folding footrests must be fitted.
(I killed "exhaust must follow original lines" because it achieves nothing.
I killed the "must meet the noise test" stuff because its already in 16c)

Pre 60 Solo. This class is intended to represent the formative era of motocross. (Weakly worded - needs input from the old hands).
16.15.7.1    The pre 60 class is for machines that closely represent those built up to (and including) 1959 models.
16.15.7.3    Front wheel travel will not exceed 178mm (7 inches) rear wheel travel will be limited to 102mm (4 inches) measured at the axle.
16.15.7.4    Plastic and fibreglass is not permitted.
16.15.7.6    Period carburettors or Amal Mk1 Concentric.
16.15.7.7 Reed valves are not permitted. (Kind of redundant, but added for clarity)

Pre 65 Solo. This class is intended to represent the first generation of purpose-built motocross bikes. (Again, weakly worded pre-amble - input please)
16.15.8.1    The pre 65 class is for machines that closely represent those that were built up to (and including) 1964 models.
16.15.8.3    Front wheel travel will not exceed 178mm (7 inches) rear wheel travel will be limited to 102mm (4 inches) measured at the axle.
16.15.8.6    Carburettors of any type pre 75 round slide may be used.
16.15.8.7 Reed valves are not permitted. (as for Pre-60)

Pre 70. This class is intended to represent the era where 4-stroke machines lost their dominance and 2-stroke machines became dominant. (Ditto)
16.15.9.1     The pre 70 class is for machines that closely represent those built up to (and including) 1969 models.
16.15.9.2     Front wheel travel will not exceed 178mm (7 inches) rear wheel travel will be limited to 102mm (4 inches) measured at the axle.
16.15.9.4     Carburettors; any type of pre 75 round slide may be used.
16.15.9.5     Reed valves are not permitted.
16.15.9.9    Yamaha XS1 and XS650 engines are eligible.
16.15.9.10    Acceptable follow on models: AJS Stormer 250; Greeves griffon models; Yamaha AT1, DT1, CT1, RT1 without reed valve induction. (tightening up the wording slightly)

Pre 75 Solo. This class is intended to represent the last of the short travel suspension era.
16.15.10.1    The pre 75 class is for machines that closely represent those built up to (and including) 1974 models.
16.15.10.2    Front wheel travel will not exceed 178mm (7 inches) rear wheel travel will be limited to 102mm (4 inches) measured at the axle.
16.15.10.4    Carburettors; any type of pre 75 round slide may be used.
16.15.10.5    XS1 and XS650 engines are eligible.
16.15.10.9    Acceptable follow on models pre 75:
Honda CR125M1, XL250K1, XL350K1, MT250 (all) and MT125 (all)
Yamaha YZ360B, DT250B,
Suzuki TS400 (all).

Pre 78 Solo and Women's Pre-78. This class is intended to represent the transition era between the short travel Pre-75 machines and the long travel Evo machines.
16.15.11.1    The pre 78 class is for machines that closely represent those built up to (and including) 1977 models.
16.15.11.2    Front wheel travel will not exceed 229mm (9 inches) rear wheel travel will be limited to 229mm (9 inches) measured at the axle. (I want to change this to 10", but in the spirit of not changing the regs, I have resisted...)
16.15.11.4    Carburettors; any type of pre 78 round slide may be used.
16.15.11.8    Acceptable follow on models pre 78

CZ 125 1978, CZ400 1978,
Montesa VB, (ditched the "must comply with suspension limits bit" because the bike has to comply with 16.15.11.2 and 16.11.1.1)
Yamaha TT500 1978 (is this correct?)

Evolution. This class is intended to represent the era of long suspension travel, before water-cooling, disc brakes and linkage rear suspension became dominant.
16.15.12.1 The Evo class is for machines that use drum brakes, air-cooling and non-linkage rear suspension, as was commonplace until 1981. It also allows for later machines up to (and including) 1985 models that retained this technology. (yes, 1985. Locking Evo into an era kills off the SexMax and any variation of it, without harming any of the 'real' Evo bikes. It still allows the later Evo Huskies, later CZs, and DT175s(!) )
e) Evolution class bikes must have No linkage suspension, No disk brakes, and Air cooled motors.
16.15.12.4    Carburettors; period flat slide carburettors and any round slide carburettor may be used.
16.15.12.9    The handlebars must be equipped with a protection pad on the cross bar. Handlebars not fitted with a cross bar must be equipped with a protection pad located in the middle of the handlebars covering the handlebar clamps. (not sure if this is supposed to be on the older eras too? Just repeating what's in the current rules).
f) Front forks must be of the non-USD type, where the fork seal(s) move with the front axle. (stops Simmons USDs and 84 KTM USDs).
(I've written this using Dave Tanner's interpretation which was basically 'we don't care if it came from a linkage/water-cooled/disc braked bike, provided the end result has drums, air and no link'. I don't personally agree, but its the closest we've got to an answer to that long running question, so I used it).

Pre 85 Solo This class is intended to represent the era of the first generation of disc front brakes, water cooling, linkage rear suspension and exhaust power valves became commonplace.
16.15.13.1    The pre 85 class is for machines that closely represent those built up to (and including) 1984 models.
16.15.13.2     Carburettors; pre-85 flat slide carburettors and any round slide carburettor may be used.
16.15.13.7    The handlebars must be equipped with a protection pad on the cross bar. Handlebars not fitted with a cross bar must be equipped with a protection pad located in the middle of the handlebars covering the handlebar clamps.

Pre 90 Solo This class is intended to represent the era where rear disc brakes, upside down forks, and the second generation of exhaust power valves became common place. (by second generation PVs, I'm talking about the multi-element ones like KIPS and HPP, rather than YPVS and ATAC).
16.15.14.1    The pre 90 class is for machines that closely represent those built up to (and including) 1989 models.
16.15.14.2    Carburettors; period flat slide carburettors and any round slide carburettor may be used.
16.15.14.7    The handlebars must be equipped with a protection pad on the cross bar. Handlebars not fitted with a cross bar must be equipped with a protection pad located in the middle of the handlebars covering the handlebar clamps.

(I know sod-all about sliders and sidecars, and there doesn't seem to be much stress around them, so I assume the rules for those are pretty well right?)
16.16 SLIDERS
16.16.1 Slider Frames
16.16.1.1    The frame must:

Have a conventional swing arm rear suspension with twin shock absorbers,
Have a front wheel diameter of 23”,
Have a rear wheel diameter of 19”,
Have rear tyres with a maximum tread pattern depth of 8mm,
Not be fitted with leading-link front forks.

16.16.2 Slider Solo Engines
16.16.2.1    The slider engine must:

Be a single cylinder,
When four stroke be 2- valve push rod operation,
Have a single spark plug,
Be vertical in the chassis,
Be fitted with a round slide carburettor, or
Be a period two stroke compatible with class entered.

16.16.3 Slider Gearbox: Classic Long Track
16.16.3.1    The gearbox must have at least two gears.
16.16.4 Slider Sidecar Frames
16.16.4.1    Conventional type frames as used prior to 31st December 1976 must be used.
16.16.5 Slider Sidecar Engines
16.16.5.1    Engines must have been manufactured before 31st December 1976.
16.17 SIDECARS
16.17.1 All Classes
16.17.1.1    Left -hand and right -hand sidecars may compete against each other in Classic Motocross.
16.17.2 Frames and Parts
16.17.2.1    For the Pre-1975 classes, all performance parts except frames must be manufactured before 31st December 1974 and must comply with the following:

Wheel track measurement, taken between the longitudinal centres of the rear and sidecar wheels must be between 810mm and 1100mm,
The minimum ground clearance must be 175mm unladen,
The maximum lean of the motorcycle at saddle height mustbe 50mm,
The dimensions of the sidecar baseboard in plain view, taken from a line drawn no further rearwards than the lowest point of the front down-tube to the forward most point of the sidecar wheel tyre and terminating no further rearwards than a line drawn at right angles to the machine from the rearmost point of the rear tyre, must be:
At least 760mm long adjacent to the sidecar wheel,
At least 300mm wide with at least 25mm radius to all corners.
There must be no more than 50mm between baseboard and motorcycle and between baseboard and sidecar wheel. The baseboard must be arranged so as not to allow the passenger’s feet to be trapped,
There must be no less than 4 sidecar attachment points,
Stirrup fitting for the passenger’s feet are not permitted,
Handholds:
Must be finished with a loop of at least 100mm,
Must not project beyond a line taken with the outer edge of the sidecar mudguard or bodywork,
Adjacent to the nose section of the sidecar and less than 200mm from the track surface must be at an angle of at least 45° from the horizontal.
The rear end of the rear wheel mudguard must terminate not more than 65° above a horizontal line drawn through the rear wheel axle and be valanced to baseboard level on the inside,
The sidecar mudguard must cover at least 135° of the periphery of the wheel and be valanced to baseboard level on the inside,
No machine may be fitted with scoop or paddle tyres,
Suspension travel must not exceed:
152mm (6”) 178mm (7”) measured at the front axle,
102mm (4”) at the rear axle.
Rear tyre width must not exceed 135mm (5.3”),
Brakes:
Front – single caliper, single disc may be fitted provided they were manufactured before 31st December 1974,
Rear – rear disc brakes may be used provided they were fitted as standard equipment for that particular combination.

Only round-slide carburettors manufactured within the relevant period may be used,
Engine capacity must be up to 1300cc.

16.17.2.2    Pre-1985 is for sidecars constructed with motors manufactured before 31st December 1984.
16.17.2.3    A lanyard operated ignition cut-out switch, operating on the primary circuit, must be fitted to the following with a maximum length of one metre:
DISCIPLINE

MACHINE
Motocross    Sidecars
Dirt track    Sidecars
16.17.2.4    Pre-1968 will be for sidecars constructed from road going frames and all major components are those commercially available within the period.
16.17.2.5    The following table sets out the machines and components which eligibility scrutineers may use as a guide in determining eligibility. Entrants must prove eligibility of machines not listed below.
MAKE

MODEL(S)
Wasp    All up to and including RT2, RT8 and RT14
Hagon    All up to 31st December 1974
Yamaha    XS 650 all models
Honda    Any K series
Norton    All 750, 850 to Mk2 only
Westlake    All up to 850cc and 31st December 1974
Triumph    All up to T150
CCM    All BSA B50 based models
Title: Re: Rule re-write.
Post by: Ted on February 09, 2014, 04:47:34 pm: No reference to Optional B arms in Pre 78?

Another state, another view
Title: Re: Rule re-write.
Post by: SON on February 09, 2014, 04:55:08 pm: Good work, well done
And you don't need to borrow a Dickhead Detector,
Not yet
Title: Re: Rule re-write.
Post by: TM BILL on February 09, 2014, 05:21:03 pm: Shit Nath you dont mess about :) as you have asked i will read properly a couple of times before making any comments .

Thanks for the effort :)
Title: Re: Rule re-write.
Post by: Nathan S on February 09, 2014, 05:23:56 pm: Son, Bill, Thanks.

I've had them written in my head for years.
41* and a sick kid have kept me inside, so I guess the planets aligned today.

Quote from: Ted on February 09, 2014, 04:47:34 pm
No reference to Optional B arms in Pre 78?

Another state, another view

Valid point, that I have been struggling with...
I believe the listed carry-over models are bikes that are officially considered to be "close enough" - stuff like the '75 CR125 cylinder, and the DT250B frame gussets & front hub, and the bit where the RT1 uses all pre-70 technology even though it didn't come out until 1970.
If they're identical to un-questioned bikes, then there's no need for them to be listed.
Same goes for the RM-B optional arm.

Maybe there should be a seperate section that lists 'contentious parts' and whether they are accepted or rejected, and why.
There is such a chart on page 7 of CAMS' Production Rally Car regs (http://docs.cams.com.au/Manual/Rally/RR11-Group-3C-PRC-2014-1.pdf). The PRC regs are an abomination and the chart always struck me as being pretty clunky, but I see its purpose...

Maybe the best way to handle such things is a formal statement from the CMX Commission?
For example: "The Commission have determined that Part X is legal for Pre-75. Part Y has been determined as not legal for Pre-75" and then include some basic info about how to identify Part X and Part Y?
Title: Re: Rule re-write.
Post by: JohnnyO on February 09, 2014, 05:49:06 pm: Good work.. Just had a quick look, I think rule 16.15.7 d) may need altering purely because most of the aftermarket alloy swingarms I have for pre 78 & Evo have the shock mounts in a different position to std for the use of different length shocks.
Title: Re: Rule re-write.
Post by: VMX247 on February 09, 2014, 06:00:37 pm: Good job Nathan... 8) Hope you get heaps of good feedback on the input you've written. :)

Someone answer why TM250 doesn't get in this follow on list ?

16.15.10.9 Acceptable follow on models pre 75:
Honda CR125M1, XL250K1, XL350K1, MT250 (all) and MT125 (all)
Yamaha YZ360B, DT250B,
Suzuki TS400 (all).
Title: Re: Rule re-write.
Post by: firko on February 09, 2014, 06:01:12 pm: Well done Nathan. I'm very happy that you've finally made a start on what I thought you should have been doing instead of offering up silly hypotheticals and empty criticisms. Despite our differences I never doubted your ability to produce sensible rewording of what we've had for 25 years. You can only offer up criticism for so long until those criticisms become empty. You need to offer an alternative and you've made a good start here........

I'm a bit snowed under with stuff as well as suffering a broken left hand (I'm left handed) so don't much feel like typing tonight. I'll have a good hard read and add any suggestions I feel might be worth consideration over the next day or two.
Title: Re: Rule re-write.
Post by: SON on February 09, 2014, 06:05:56 pm: I like The Contentious items list idea
Title: Re: Rule re-write.
Post by: Nathan S on February 09, 2014, 06:17:10 pm: JohnnyO, interesting point.
There is a conflict there - it's sort of difficult to define the "original mounting point" on a non-original part - and I had intended that the original mounting points on aftermarket arms would be ok, but it is not obvious.

More thought required.
Title: Re: Rule re-write.
Post by: Davey Crocket on February 09, 2014, 06:29:16 pm: Well done Nathan, we've had this conversation before so you know where I'm at.....Alison, 75 TM models not a carry over because the frame is changed and it has more rear wheel travel.
Title: Re: Rule re-write.
Post by: Slakewell on February 09, 2014, 06:44:17 pm: It is my belief that the suspension limit rule for pre 78 is just removed. Same as the mounting points stuff. My argument is that any major raising of suspension lengths for pre 78 makes the bike handle so badly that it slows them down. Forks must be manufacture before 78.
Title: Re: Rule re-write.
Post by: Lozza on February 09, 2014, 06:51:37 pm: I would 16.15.7.(ba) to "operationaly similar and visualy indistinguishable" other than that pretty much complete
Title: Re: Rule re-write.
Post by: JohnnyO on February 09, 2014, 07:00:19 pm: I would actually like to see the shock mount rule removed altogether for pre 78 to allow bikes like the 75 Maico & TM Suzuki, 75/76 CR250 & KX250/400 to have the rear end modified for more travel like they did back in the day and make them competitive.
It's really no different to buying a aftermarket C&J or Profab frame with more suspension travel than the original frame..
Title: Re: Rule re-write.
Post by: Nathan S on February 09, 2014, 07:01:02 pm: Quote from: Slakewell on February 09, 2014, 06:44:17 pm
It is my belief that the suspension limit rule for pre 78 is just removed. Same as the mounting points stuff. My argument is that any major raising of suspension lengths for pre 78 makes the bike handle so badly that it slows them down. Forks must be manufacture before 78.

Not my experience. I built a YZ125D with a lengthened shock and 250D forks. It was limited back to 9" of travel, but sat like an Evo bike. It was brilliant everywhere.
Ditto my YZ125D with 125G forks (even though the G forks flex like drinking straws).

Anyone else got input on this?
Title: Re: Rule re-write.
Post by: evo550 on February 09, 2014, 07:06:46 pm: Am I right in assuming the Evo rules you've written will now allow CR500 motors in Twin shock 250 chassis with 50mm magnum forks ?
Title: Re: Rule re-write.
Post by: Ted on February 09, 2014, 07:08:52 pm: Well just after paying big bucks for 9 inch travel shocks for Pre 78 to be made and forks to suit I won't be voting for 10 inches. I think that's understandable.
Title: Re: Rule re-write.
Post by: Nathan S on February 09, 2014, 07:20:40 pm: Quote from: evo550 on February 09, 2014, 07:06:46 pm
Am I right in assuming the Evo rules you've written will now allow CR500 motors in Twin shock 250 chassis with 50mm magnum forks ?

Engine Yes (as per Dave Tanner's comments in the other thread);
Forks No (as per 16.15.7a and 16.15.12.1).

I don't personally agree on the motor thing. I just went with what DT said in the other thread. It can be changed to limit motors and/or forks to being from Evo bikes.
Title: Re: Rule re-write.
Post by: Ted on February 09, 2014, 07:24:35 pm: Cannot you write NO parts to be used from a LINKAGED, WATER COOLED, DISC BRAKE bike

Lose his train of thought altogether

Basically what you are proposing is Pre 85 drum brake class and Pre 85 disk brake class
Title: Re: Rule re-write.
Post by: Slakewell on February 09, 2014, 07:24:50 pm: Given that the pre 78 Nats race on mostly smooth tracks having extra travel is mitigated and those bikes at the pointy end like Ted's RM with 9" would still be competitive. Focus on the fact that most bikes don't fit in the rules in standard trim and some wont modify there bikes to comply.
Title: Re: Rule re-write.
Post by: Nathan S on February 09, 2014, 07:25:19 pm: Quote from: Lozza on February 09, 2014, 06:51:37 pm
I would 16.15.7.(ba) to "operationaly similar and visualy indistinguishable" other than that pretty much complete

Why?
Title: Re: Rule re-write.
Post by: TM BILL on February 09, 2014, 07:30:12 pm: Quote from: JohnnyO on February 09, 2014, 07:00:19 pm
I would actually like to see the shock mount rule removed altogether for pre 78 to allow bikes like the 75 Maico & TM Suzuki, 75/76 CR250 & KX250/400 to have the rear end modified for more travel like they did back in the day and make them competitive.
It's really no different to buying a aftermarket C&J or Profab frame with more suspension travel than the original frame..

Agreed it makes sense and it was done in the day
Title: Re: Rule re-write.
Post by: Nathan S on February 09, 2014, 07:31:53 pm: Quote from: Ted on February 09, 2014, 07:24:35 pm
Cannot you write NO parts to be used from a LINKAGED, WATER COOLED, DISC BRAKE bike

Lose his train of thought altogether

Basically what you are proposing is Pre 85 drum brake class and Pre 85 disk brake class

Well, it is a Pre-86 drum brake, air-cooled, no-linkage class...

And it's not my proposal - I've been trying to leave my own opinions out of it. I went with the closest thing we've had to a clear answer on the unanswerable question about Evo.
Its a seperate discussion that DOES need to happen - but not in this thread.
Title: Re: Rule re-write.
Post by: Ted on February 09, 2014, 07:54:57 pm: Quote from: TM bill on February 09, 2014, 07:30:12 pm
Quote from: JohnnyO on February 09, 2014, 07:00:19 pm
I would actually like to see the shock mount rule removed altogether for pre 78 to allow bikes like the 75 Maico & TM Suzuki, 75/76 CR250 & KX250/400 to have the rear end modified for more travel like they did back in the day and make them competitive.
It's really no different to buying a aftermarket C&J or Profab frame with more suspension travel than the original frame..

Agreed it makes sense and it was done in the day

But doesn't it say OEM. If they require more travel buy a bike with it or buy a aftermarket frame. Cutting up mounts can only lead to a bitch class.
Title: Re: Rule re-write.
Post by: Ted on February 09, 2014, 08:02:23 pm: Quote from: Slakewell on February 09, 2014, 07:24:50 pm
Given that the pre 78 Nats race on mostly smooth tracks having extra travel is mitigated and those bikes at the pointy end like Ted's RM with 9" would still be competitive. Focus on the fact that most bikes don't fit in the rules in standard trim and some wont modify there bikes to comply.

Mick, my bike didn't comply either. It only had 8 inches. 95% of the field would struggle to get anywhere near 9 inches standard. Euros may be different but they don't make up MOST of the field.
Title: Re: Rule re-write.
Post by: oldfart on February 09, 2014, 08:17:53 pm: Nathan .... I think it's all covered in 2.5.9.1 and 1.2.0.1
Title: Re: Rule re-write.
Post by: evo550 on February 09, 2014, 08:30:33 pm: Quote from: Nathan S on February 09, 2014, 07:20:40 pm
Quote from: evo550 on February 09, 2014, 07:06:46 pm
Am I right in assuming the Evo rules you've written will now allow CR500 motors in Twin shock 250 chassis with 50mm magnum forks ?

Engine Yes (as per Dave Tanner's comments in the other thread);
Forks No (as per 16.15.7a and 16.15.12.1).

I don't personally agree on the motor thing. I just went with what DT said in the other thread. It can be changed to limit motors and/or forks to being from Evo bikes.

16.15.12.1 The Evo class is for machines that closely represent those built up to (and including) 1985 models.

Ok, Firstly, not my idea of an Evo class. I don't agree with the interpretation in the other thread, that being said it's your proposal. You might want to change the wording in 16.15.12.1 to something along the lines of "must not comprise of any major components manufactured after dec 31 198?"
The "closely represents" bit leaves the rule wide open for interpretation.
Title: Re: Rule re-write.
Post by: JohnnyO on February 09, 2014, 08:51:41 pm: Quote from: Ted on February 09, 2014, 07:54:57 pm
Quote from: TM bill on February 09, 2014, 07:30:12 pm
Quote from: JohnnyO on February 09, 2014, 07:00:19 pm
I would actually like to see the shock mount rule removed altogether for pre 78 to allow bikes like the 75 Maico & TM Suzuki, 75/76 CR250 & KX250/400 to have the rear end modified for more travel like they did back in the day and make them competitive.
It's really no different to buying a aftermarket C&J or Profab frame with more suspension travel than the original frame..

Agreed it makes sense and it was done in the day

But doesn't it say OEM. If they require more travel buy a bike with it or buy a aftermarket frame. Cutting up mounts can only lead to a bitch class.
I'm guessing you had nothing to do with mx in the mid 70's..
Title: Re: Rule re-write.
Post by: Ted on February 09, 2014, 09:01:17 pm: On the contrary John. 74 75 LMORCC 76 77 HAWKESBURY MCC then enduro HAWKESBURY MCC

John, I don't think cutting up bikes to alter suspension travel to make them more competitive is the way to go Improve them by all means but not moving mounts.
Title: Re: Rule re-write.
Post by: Nathan S on February 09, 2014, 09:07:16 pm: Quote from: oldfart on February 09, 2014, 08:17:53 pm
Nathan .... I think it's all covered in 2.5.9.1 and 1.2.0.1

???
Quote
2.5.9.1 In carrying out their duties, operational officials must:

At the beginning of the meeting report to the Clerk of the Course for instructions,
Only use apparatus authorised under these Rules,
Provide the Clerk of Course with reports as required,
Comply with the directions and instructions of the Steward/Referee and the Clerk of Course.

Quote
1.2.0.1 The purpose of these Rules is to regulate and control motorcycle competition.

The Rules are to be interpreted with the intent that competition will be safe, free and fair and conducted applying the principles of natural justice,
The Rules are Competition Rules made under clause 71 of the Constitution,
The Rules, and any determination made under them and in accordance with them, bind all Controlling Bodies and all participants in the sport.
Title: Re: Rule re-write.
Post by: JohnnyO on February 09, 2014, 09:11:33 pm: I was just remembering it as it was in the day Ted with a majority of bikes having laid down shocks in the mid 70's.. ala Gary Flood, Mark Pace, Graeme Smythe etc.
Thought it might encourage a few more 75/76 models onto the track.. Then again most people in vmx didn't race in the 70's let alone remember it!
Title: Re: Rule re-write.
Post by: Nathan S on February 09, 2014, 09:21:25 pm: Quote from: evo550 on February 09, 2014, 08:30:33 pm
16.15.12.1 The Evo class is for machines that closely represent those built up to (and including) 1985 models.

Ok, Firstly, not my idea of an Evo class. I don't agree with the interpretation in the other thread, that being said it's your proposal.

You might want to change the wording in 16.15.12.1 to something along the lines of "must not comprise of any major components manufactured after dec 31 198?"
The "closely represents" bit leaves the rule wide open for interpretation.

Point taken.
16.15.12.1 changed to "The Evo class is for machines that use the drum brakes, air-cooling and non-linkage rear suspension, as was commonplace until 1981. It also allows for later machines up to (and including) 1985 models that retained this technology".

I too, disagree with DT's definition, but his is the most official that we have to work with, and my intention was not to alter what is (or is not) legal.
If the most official definiton changes, then I'm more than happy to rework what I've done.
Title: Re: Rule re-write.
Post by: SON on February 09, 2014, 09:22:00 pm: John, some we laid down others we stood upright.
Either way we chased long travel even if it was under damped.
Title: Re: Rule re-write.
Post by: DJRacing on February 09, 2014, 09:23:41 pm: Nathan, excellent work. I hope that everyone reads them and replies with sensible questions and answers.

e) Evolution class bikes must have No linkage suspension, No disk brakes, and Air cooled motors.
Could this be worded a little different so that it leaves in no doubt what it means?
Maybe,
Evolution class bikes must have been manufactured with Twinshocked or cantilevered rear suspension and Aircooled motors and Drumbrakes. All parts from those bikes are permissible as are after-market parts of this era.
a) Modifying your bike with other major parts from a different technology or era is not allowed.

Yes I know it's long winded but it is very self explanatory and I think very water tight. Anyway just a thought and obviously open for discussion re the old and new interpretation of the existing rules.
Title: Re: Rule re-write.
Post by: Ted on February 09, 2014, 09:24:25 pm: John, I am aware of the stars back then and their trick bikes. Unfortunately for broke arse mutha fukas like us 16/17 year old kids who scraped together just enough money for the bike and that was it. In the early seventies a wave went right thru Australia. That was MX on affordable, reliable race bikes. Gone forever were the AJ and Matcho 500's you spent all day pushing. Deltek's became obsolete as well. You could buy brand new Jap bikes for under a months pay. The average Joe, and there were thousands of us were quite happy with our new rides.

I feel to change bikes for performance in 2014 is losing history.
Title: Re: Rule re-write.
Post by: Tim754 on February 09, 2014, 09:28:15 pm: Nathan your work here is serious . Thank you for your time . :)

One that will stay and should never change.

16.11.1.2 The onus of proof of eligibility shall rest wholly upon the rider or entrant of the machine. Service and parts manual publication dates are not proof of eligibility
Title: Re: Rule re-write.
Post by: DJRacing on February 09, 2014, 09:33:53 pm: 16.15.11.1 The pre 78 class is for machines that closely represent those built up to (and including) 1977 models.

I take it that you can now modify a pre75 bike to race in Pre 78 ?
Title: Re: Rule re-write.
Post by: Nathan S on February 09, 2014, 09:39:22 pm: Quote from: JohnnyO on February 09, 2014, 09:11:33 pm
I was just remembering it as it was in the day Ted with a majority of bikes having laid down shocks in the mid 70's.. ala Gary Flood, Mark Pace, Graeme Smythe etc.
Thought it might encourage a few more 75/76 models onto the track.. Then again most people in vmx didn't race in the 70's let alone remember it!

Why hasn't anyone mentioned this before!? >:( .... ;D

It's a fair point, though.
Is it worth changing the rules for? It's been "wrong" since the start of the Pre-78 class. Has it ever mattered?
Title: Re: Rule re-write.
Post by: Nathan S on February 09, 2014, 09:43:59 pm: Quote from: DJRacing on February 09, 2014, 09:33:53 pm
I take it that you can now modify a pre75 bike to race in Pre 78 ?

That was the idea. The existing rules are unworkable, in that if you have a '74 model bike with a 75 model motor or forks (or whatever), it has to run as an Evo bike. The "75/76/77 models only" rule served no useful purpose, and created some unresolvable situations.

This ties in with Johnny O's point about modded shock mounts... Personally, I think that pre-75 bikes with lay-down rear shocks should be allowed to run in Pre-78. But I wasn't trying to change the rules, just make them clearer and simpler.
Title: Re: Rule re-write.
Post by: DJRacing on February 09, 2014, 09:53:50 pm: Quote from: Nathan S on February 09, 2014, 09:43:59 pm
Quote from: DJRacing on February 09, 2014, 09:33:53 pm
I take it that you can now modify a pre75 bike to race in Pre 78 ?

That was the idea. The existing rules are unworkable, in that if you have a '74 model bike with a 75 model motor or forks (or whatever), it has to run as an Evo bike. The "75/76/77 models only" rule served no useful purpose, and created some unresolvable situations.

This ties in with Johnny O's point about modded shock mounts... Personally, I think that pre-75 bikes with lay-down rear shocks should be allowed to run in Pre-78. But I wasn't trying to change the rules, just make them clearer and simpler.

Totally agree with you on that.

16.15.8.5 Engines and gearboxes must remain externally unchanged.
Could this have a small exception to the rule ??

16.15.8.5 Engines and gearboxes must remain externally unchanged unless a two stroke oil pump has been removed ??
Title: Re: Rule re-write.
Post by: Ted on February 09, 2014, 09:58:16 pm: Quote from: JohnnyO on February 09, 2014, 09:11:33 pm
I was just remembering it as it was in the day Ted with a majority of bikes having laid down shocks in the mid 70's.. ala Gary Flood, Mark Pace, Graeme Smythe etc.
Thought it might encourage a few more 75/76 models onto the track.. Then again most people in vmx didn't race in the 70's let alone remember it!

I was at Amaroo Park the day Gaston gave us a riding lesson. The same day Camel came out of the chicane on the back wheel, over the jump on the back wheel, landing on the back wheel and only putting it down to go around the corner. Was there to see Gary Fllod fu...ck up a start at MR MX and lay his bike ( bultaco i think ) across the start line, refusing to move it until they started the race again. Which they did. I used to watch Lester Rowley ride his CCM. Hans on his Husky. I was racing there in 75 /76 , can't recall, when Christ Cater rode my 125 S in a race, breaking the clutch perch in a fall. He gets the bike home in second place then walks over to a club member who has finished racing and orders him to remove his clutch perch and give it to me as I had one race to go. Which he did.

lucky Lucy in the Sky with Diamonds wasn't as mainstream then as I would probably put it all down to a hallucination.
Title: Re: Rule re-write.
Post by: Nathan S on February 09, 2014, 10:08:16 pm: Quote from: DJRacing on February 09, 2014, 09:53:50 pm
Totally agree with you on that.

16.15.8.5 Engines and gearboxes must remain externally unchanged.
Could this have a small exception to the rule ??

16.15.8.5 Engines and gearboxes must remain externally unchanged unless a two stroke oil pump has been removed ??

16.15.8.5 has been removed in the proposed changes.
Its function has been replaced by 16.15.7 b & ba (and by the preamble for each class [16.15.x.1]).
Title: Re: Rule re-write.
Post by: Davey Crocket on February 09, 2014, 10:11:28 pm: Leave the pre78 class alone, 9 inches is plenty, not everybody wants to cut up a perfectly good bike to give it more travel....and de-value it at the same time. If you change the travel to 10 inches, you will loose more bikes than you gain. This is not 20/20 cricket. If you put a pre75 bike next to a pre78 and EVO you can see a remarked difference....it looks right to the punters as far as telling them apart, give pre78 more travel and they will look like EVO bikes. EVO should not have any parts off a linkage bike, including making 1979 CR500's etc. Remember the more rules, the more drama's, generally it's only minor tweaks that need to happen. Don't forget the 2004 KX500 in pre90 ;). ;).I would like to see period water cooled kits being allowed to be used, lets face it, they probably add 5kg's to the bike [and on the forks where you don't want it], they wont be any advantage as we mostly do 3/4 lap races and 6/7 at the Nats...in real terms they will probably make the bike slower. No home made kits though or adapting later model parts to fit. I think it would add some "cool" to our sport.....maybe there are other period mods that where done that aren't allowed that could be?. I don't think swingarms/frames need to have shock mounts altered, most bikes can get extra travel by putting longer shocks on. Some of the bikes that turn up to meetings would scare the crap out of me if I was in the same race and knew oldmate that couldn't weld to save himself had just added long travel suspension to his bike with his $6.95 welder he just bought from Aldi and was now testing it....when it goes bang and takes out half the field....who is responsible, I as a qualified scrutineer would run a hundred miles at seeing a home LTR conversion....you would put clubs in a bad situation and I'm sure MA would not be happy Jan..... Remember, we are in the age of litigation fella's, even re-writing these rules you would want a disclaimer....protect yourself and the club....and before the Kiwi's jump on board, NZ is a totally different kettle of fish than Australia.
Title: Re: Rule re-write.
Post by: FourstrokeForever on February 09, 2014, 10:19:39 pm: Nathan, you have done an excellent job on a very thankless task. There will be be more knockers than those that want to work with you. Kudos to you for looking at ruling chapters and including them in your proposed re-write. 090 was right, you are the man for the job!
Quote from: Nathan S on February 09, 2014, 09:39:22 pm
Quote from: JohnnyO on February 09, 2014, 09:11:33 pm
I was just remembering it as it was in the day Ted with a majority of bikes having laid down shocks in the mid 70's.. ala Gary Flood, Mark Pace, Graeme Smythe etc.
Thought it might encourage a few more 75/76 models onto the track.. Then again most people in vmx didn't race in the 70's let alone remember it!

Why hasn't anyone mentioned this before!? >:( .... ;D

It's a fair point, though.
Is it worth changing the rules for? It's been "wrong" since the start of the Pre-78 class. Has it ever mattered?

I have thought the same thing for ages. Not just later pre78 bikes, but earlier '75 and '76 models that were basically the same as '74's and in some cases, were worse handling bikes. No body wants to race them in pre78.

I think re-writting to state that "the frames original shock mount position must be retained" could alleviate some confusion. Then add something like, "the swinging arm shock location is open to any position as long as the swinging arm is of the same era as the machine"
All pre 78 machines must comply with 9" travel front and rear, measured at the axle to the lower point of the lower fork clamp area for the front wheel travel, springs removed and bottomed to full travel, and from lower rear shock mounting bolt to top rear shock mounting bolt for rear wheel travel, springs removed and bottomed to full travel.

Good luck on your mission and if there is any help you need, let me know.
Title: Re: Rule re-write.
Post by: JohnnyO on February 09, 2014, 10:28:09 pm: Davey many of the 75/76 models only have 6 or maybe 7" rear wheel travel, my idea was to allow owners to bring those bikes up to the 9" class limit not make them 12".
There's enough knowledge and tradesmen around to do that mod properly, most people in vmx don't mind spending a bit of coin to get a job done properly..
Title: Re: Rule re-write.
Post by: JohnnyO on February 09, 2014, 10:33:34 pm: Quote from: Ted on February 09, 2014, 09:58:16 pm
Quote from: JohnnyO on February 09, 2014, 09:11:33 pm
I was just remembering it as it was in the day Ted with a majority of bikes having laid down shocks in the mid 70's.. ala Gary Flood, Mark Pace, Graeme Smythe etc.
Thought it might encourage a few more 75/76 models onto the track.. Then again most people in vmx didn't race in the 70's let alone remember it!

I was at Amaroo Park the day Gaston gave us a riding lesson. The same day Camel came out of the chicane on the back wheel, over the jump on the back wheel, landing on the back wheel and only putting it down to go around the corner. Was there to see Gary Fllod fu...ck up a start at MR MX and lay his bike ( bultaco i think ) across the start line, refusing to move it until they started the race again. Which they did. I used to watch Lester Rowley ride his CCM. Hans on his Husky. I was racing there in 75 /76 , can't recall, when Christ Cater rode my 125 S in a race, breaking the clutch perch in a fall. He gets the bike home in second place then walks over to a club member who has finished racing and orders him to remove his clutch perch and give it to me as I had one race to go. Which he did.

lucky Lucy in the Sky with Diamonds wasn't as mainstream then as I would probably put it all down to a hallucination.
Ted good to hear you were around mx in that era, they were glory days..
I saw those guys and many more legends ride in Qld in that period..
Title: Re: Rule re-write.
Post by: Lozza on February 09, 2014, 10:34:06 pm: Quote from: Nathan S on February 09, 2014, 07:25:19 pm
Quote from: Lozza on February 09, 2014, 06:51:37 pm
I would 16.15.7.(ba) to "operationaly similar and visualy indistinguishable" other than that pretty much complete

Why?

Indistiguishable is clear and defined , 'similar' is open to interpretation. Similar operation means things like I could not convert a powervalve to servo operation from governed off the crank. here is an example

Quote from: Davey Crocket on February 09, 2014, 10:11:28 pm
I would like to see period water cooled kits being allowed to be used, lets face it, they probably add 5kg's to the bike [and on the forks where you don't want it], they wont be any advantage as we mostly do 3/4 lap races and 6/7 at the Nats...in real terms they will probably make the bike slower. No home made kits though or adapting later model parts to fit. I think it would add some "cool" to our sport.....maybe there are other period mods that where done that aren't allowed that could be?
Rider/tuners/factories were cutting off air cooled cylinder fins and welding on water jackets on in the 1930's, Bultaco TSS road racers used thermo syphon water cooling in the 60's. I see no reason why a home made kit should not be disallowed so long as the competitor had evidence it was raced in the period it was 'indistinguishable' from what was used in or before the period and functioned in a similar way.

or

just get log books

The whole trust of the rules should be to stop people going to great lengths to adapt later model parts to major components.
Title: Re: Rule re-write.
Post by: DJRacing on February 09, 2014, 10:37:59 pm: Quote from: Davey Crocket on February 09, 2014, 10:11:28 pm
Leave the pre78 class alone, 9 inches is plenty, not everybody wants to cut up a perfectly good bike to give it more travel....and de-value it at the same time. If you change the travel to 10 inches, you will loose more bikes than you gain. This is not 20/20 cricket. If you put a pre75 bike next to a pre78 and EVO you can see a remarked difference....it looks right to the punters as far as telling them apart, give pre78 more travel and they will look like EVO bikes. EVO should not have any parts off a linkage bike, including making 1979 CR500's etc. Remember the more rules, the more drama's, generally it's only minor tweaks that need to happen. Don't forget the 2004 KX500 in pre90 ;). ;).I would like to see period water cooled kits being allowed to be used, lets face it, they probably add 5kg's to the bike [and on the forks where you don't want it], they wont be any advantage as we mostly do 3/4 lap races and 6/7 at the Nats...in real terms they will probably make the bike slower. No home made kits though or adapting later model parts to fit. I think it would add some "cool" to our sport.....maybe there are other period mods that where done that aren't allowed that could be?. I don't think swingarms/frames need to have shock mounts altered, most bikes can get extra travel by putting longer shocks on. Some of the bikes that turn up to meetings would scare the crap out of me if I was in the same race and knew oldmate that couldn't weld to save himself had just added long travel suspension to his bike with his $6.95 welder he just bought from Aldi and was now testing it....when it goes bang and takes out half the field....who is responsible, I as a qualified scrutineer would run a hundred miles at seeing a home LTR conversion....you would put clubs in a bad situation and I'm sure MA would not be happy Jan..... Remember, we are in the age of litigation fella's, even re-writing these rules you would want a disclaimer....protect yourself and the club....and before the Kiwi's jump on board, NZ is a totally different kettle of fish than Australia.

All good points John but this kiwi has already been on-board for a while ;D
What ever the out come of this, the rules need to be very clear and self explanatory for the newbie (not the old hands) so once read they can walk away knowing what classes a bike fits into as well as what can and can't be done to a VMX bike. There should be no asking of what rule 16.......... means.
Title: Re: Rule re-write.
Post by: JohnnyO on February 09, 2014, 10:55:15 pm: Quote from: Davey Crocket on February 09, 2014, 10:11:28 pm
I would like to see period water cooled kits being allowed to be used, lets face it, they probably add 5kg's to the bike [and on the forks where you don't want it], they wont be any advantage as we mostly do 3/4 lap races and 6/7 at the Nats...in real terms they will probably make the bike slower. No home made kits though or adapting later model parts to fit. I think it would add some "cool" to our sport.....maybe there are other period mods that where done that aren't allowed that could be?
Yep I'd like to see those Shinobi, Mugen, Fox etc water cooled kits included and made legal, they were a part of motocross history and another of the things that made 70's mx so cool..
Then I could use the Shinobi kit I have for a 76 CR125! :D
Title: Re: Rule re-write.
Post by: John Orchard on February 09, 2014, 11:03:12 pm: Skunkworks
Title: Re: Rule re-write.
Post by: Ted on February 09, 2014, 11:14:14 pm: Quote from: JohnnyO on February 09, 2014, 10:55:15 pm

Quote from: Davey Crocket on February 09, 2014, 10:11:28 pm
I would like to see period water cooled kits being allowed to be used, lets face it, they probably add 5kg's to the bike [and on the forks where you don't want it], they wont be any advantage as we mostly do 3/4 lap races and 6/7 at the Nats...in real terms they will probably make the bike slower. No home made kits though or adapting later model parts to fit. I think it would add some "cool" to our sport.....maybe there are other period mods that where done that aren't allowed that could be?
Yep I'd like to see those Shinobi, Mugen, Fox etc water cooled kits included and made legal, they were a part of motocross history and another of the things that made 70's mx so cool..
Then I could use the Shinobi kit I have for a 76 CR125! :D

In a 4 lap 10 minute race would it be of benefit? Well set up bikes don't get that hot in such short races. 45 minute moto it would. I'm thinking the weight of it plus water would detract rather than enhance performance in a 10 min race. Be cool to see it though.
Title: Re: Rule re-write.
Post by: evo550 on February 09, 2014, 11:27:40 pm: Quote from: JohnnyO on February 09, 2014, 10:55:15 pm

Quote from: Davey Crocket on February 09, 2014, 10:11:28 pm
I would like to see period water cooled kits being allowed to be used, lets face it, they probably add 5kg's to the bike [and on the forks where you don't want it], they wont be any advantage as we mostly do 3/4 lap races and 6/7 at the Nats...in real terms they will probably make the bike slower. No home made kits though or adapting later model parts to fit. I think it would add some "cool" to our sport.....maybe there are other period mods that where done that aren't allowed that could be?
Yep I'd like to see those Shinobi, Mugen, Fox etc water cooled kits included and made legal, they were a part of motocross history and another of the things that made 70's mx so cool..
Then I could use the Shinobi kit I have for a 76 CR125! :D

Where does it say you can't use those ? Evo is the only class that stipulates air cooled only...
Title: Re: Rule re-write.
Post by: Davey Crocket on February 09, 2014, 11:29:20 pm: That's my point Ted, they would be no real advantage and most kits where for 125's where weight is a huge factor....if they where that good, everyone would have had one.
Title: Re: Rule re-write.
Post by: JohnnyO on February 09, 2014, 11:51:45 pm: Quote from: Ted on February 09, 2014, 11:14:14 pm
Quote from: JohnnyO on February 09, 2014, 10:55:15 pm

Quote from: Davey Crocket on February 09, 2014, 10:11:28 pm
I would like to see period water cooled kits being allowed to be used, lets face it, they probably add 5kg's to the bike [and on the forks where you don't want it], they wont be any advantage as we mostly do 3/4 lap races and 6/7 at the Nats...in real terms they will probably make the bike slower. No home made kits though or adapting later model parts to fit. I think it would add some "cool" to our sport.....maybe there are other period mods that where done that aren't allowed that could be?
Yep I'd like to see those Shinobi, Mugen, Fox etc water cooled kits included and made legal, they were a part of motocross history and another of the things that made 70's mx so cool..
Then I could use the Shinobi kit I have for a 76 CR125! :D

In a 4 lap 10 minute race would it be of benefit? Well set up bikes don't get that hot in such short races. 45 minute moto it would. I'm thinking the weight of it plus water would detract rather than enhance performance in a 10 min race. Be cool to see it though.
It's all about having a 'trick' for the period bike Ted. You know..Fox Airshox, DG alloy swingarm, Simons forks, Shinobi water cooled head, none of it makes us any faster but jeez it looks cool!!
Title: Re: Rule re-write.
Post by: Michael Moore on February 10, 2014, 04:32:07 am: Nathan's proposals mostly look pretty reasonable to me. As an interested bystander (since I'm unlikely to ever get Down Under to race) I'm puzzled by the insistence on stock or OEM specifications on the bikes. Stock motorcycles are boring, who wants to bother with them when you can have something really cool? :)

Here in the USA when LT suspension came in there were lots of people who were modifying their bikes. Moved up dampers, laid down dampers, Wheelsmith slider extensions on Maico forks, Competition Dynamics kits to monoshock your twinshock, bent swing arms, braced swing arms, custom swing arms, custom frames and on and on and on. The magazines had multiple articles on the conversion processes, including on trials bikes like the Bultaco Sherpa T. You could buy different seats, tanks, fenders, airboxes etc so bikes that didn't look very stock were pretty common.

There were also a fair number of people who had access to machine tools at work or had well-equipped shops at home (look at people like Harry Hindall and others in the SoCal aerospace industry areas or Joe Bolger) who would make very cool/trick one-offs. Make your own frame, make your own wheel hubs, graft on outboard motor reed valves, borrow dampers from race cars, wrap a water jacket around a cylinder or head, may not have been common, but it certainly happened.

It may make sense to exclude some obviously later out-of-period parts like more modern and effective large diameter teleforks, but I can't see why any small TLS front drum should be a problem -- any MX drum brake is pretty much functionally the same as another as there's only so much improvement that can be gotten out of them and if you look around there were some small TLS (or even 4LS) brakes available in the 60s and 70s. Van Tech sold their own floating backing plate assemblies for OEM hubs and I think Wheelsmith may have too. It wouldn't be an insurmountable task for someone to grab cams/levers from a couple of SLS brakes and make their own TLS backing plate.

While I have my gripes with some of the AHRMA rules it does seem to work pretty well to have a maximum travel rule for the different period classes, and how a bike achieves that is largely immaterial as it is likely that someone tried just about everything back in the day. If someone can make a Skunk Works link and some moved up damper mounts work for them within the allowed travel, more power to them. Once you start saying "OEM this or that" you start opening up a can of enforcement worms. This is racing, not a concours d'elegance where people lose points for using the left-handed prawn nut on their bike made on 02 May 1965 when everyone knows that was only fitted to bikes made on 30 April 1965.

Perhaps if you required "any technology available in the period, any drum brake wheel assembly accepted, max suspension travel XXX, max stanchion OD on RSU telefork of XXX" and left it at that you'd have fewer people wondering about the legality of their particular cool part. You could also have "must present a general appearance evocative of the period" to preclude people putting a 1985 "snail" expansion chamber on their Greeves Challenger. I think most people can agree about "that looks appropriate" issues that are based on cosmetic appearances and not technical issues. If the bike looks good to Joe or Jane Average Person from 20 feet, it is good.

Keep the rules as simple and broad as you can and you'll cut down the grumbling and complaints.

cheers,
Michael
Title: Re: Rule re-write.
Post by: JohnnyO on February 10, 2014, 07:03:43 am: Some very good points there Michael Moore and that OEM rule doesn't sit well with me either, most people don't even understand its meaning anyway.
Some people on here are killing off the history of our sport by not wanting bikes to be setup as they were thru the 70's, but instead wanting every bike to appear as it did in the sales brochure..
Most people don't even know the shock mount rule exists so to remove the rule is going to make no difference, but it will allow the smart bike builder to perform a cool period suspension mod if they wish to. I think that rule should also be excluded from Evo as well, there are other rules stating no later single shock frame can be modified to twin shock specs.
You're totally dreaming if you think scores of people are going to rush out and buy a cheap welder and do a bodgy modification on their frame.
There is the odd bike out there racing now in both pre 78 and Evo with modified shock mounts that I'm sure the owner is unaware of the ruling and you nazis on here haven't even noticed and I'm not about to tell you either.. To exclude them would be cruel when they've done such a nice job with their bikes!
Title: Re: Rule re-write.
Post by: Nathan S on February 10, 2014, 08:22:31 am: On the shock mount thing:

The Pre-75 class is supposed to be about the short travel era, rather than the year 1974.
We all know that in the mid 70s, lots of bikes had their shock mounts modified for longer travel. That's absolutely part of MX history, but the idea of the Pre-75 class is to represent the era BEFORE that started happening. This is why GP Maicos, 74 KTMs and YZ-Bs need to have their travel shortened to race in Pre-75 - even though they meet the age cut off.

So I have no issue with the "stock shock locations" rule for Pre-75.

Obviously, for the Evo and newer eras, the need to move shock positions around has disappeared.

Which leaves Pre-78 as the class that needs more thought - this is the era where shock mounts were moved, often. To prohibit that modification now, is historically INaccurate. It's ironic that an original, unmodified-since-it-was-last-raced old race bike doesn't fit anywhere in the VMX rules.

Then again, the rules have been like that for a while - has it actually been a problem for anyone? Or are we discussing a hypothetical that doesn't really exist?
Title: Re: Rule re-write.
Post by: JohnnyO on February 10, 2014, 08:32:36 am: Nathan I do know of a couple of pre 78 and Evo bikes with the shock mounts moved, it's just that no one has picked up on it. Would hate to see them excluded because they are unaware of the rule and they are nicely done mods hence not looking out of place and also going un noticed.
I agree 100% pre 75 should have the shock mount rule due to the 4" travel requirement.
Title: Re: Rule re-write.
Post by: FourstrokeForever on February 10, 2014, 08:38:24 am: Quote from: JohnnyO on February 10, 2014, 07:03:43 am
Some very good points there Michael Moore and that OEM rule doesn't sit well with me either, most people don't even understand its meaning anyway.
Some people on here are killing off the history of our sport by not wanting bikes to be setup as they were thru the 70's, but instead wanting every bike to appear as it did in the sales brochure..
Most people don't even know the shock mount rule exists so to remove the rule is going to make no difference, but it will allow the smart bike builder to perform a cool period suspension mod if they wish to. I think that rule should also be excluded from Evo as well, there are other rules stating no later single shock frame can be modified to twin shock specs.
You're totally dreaming if you think scores of people are going to rush out and buy a cheap welder and do a bodgy modification on their frame.
There is the odd bike out there racing now in both pre 78 and Evo with modified shock mounts that I'm sure the owner is unaware of the ruling and you nazis on here haven't even noticed and I'm not about to tell you either.. To exclude them would be cruel when they've done such a nice job with their bikes!

Well said Johnny and Micheal Moore. Bikes of all types have been getting modified since the day they rolled out of a factory. Many people had different ideas on how to make a bike work better. Some time it worked, other times it made the bike no better at all. The point is as Micheal Moore stated. We are not entering a bike into a concours d'elegance. We build bikes to race and look good while we're at it. Yet it seems the boffins at MA want us to build a bike exactly as it came out of the dealership so we can then flog it on a race track. Many bikes builds of yesteryear had modified shock positions and swingarms. C&J, HPF, JBS, CCM, Hindall, and many more built custom frames for their customers. DG, FMF, Profab, Whitline, Wheelsmith and others made specialist parts so the punters could easily modify their suspension and motors without the need for a high level mechanic or engineer. All you had to do was bolt it on and sort the bike to your liking.
Period "trick" bikes make a whole world of sense to me. And they are great to look at.
Title: Re: Rule re-write.
Post by: FourstrokeForever on February 10, 2014, 08:45:07 am: Quote from: Nathan S on February 10, 2014, 08:22:31 am
On the shock mount thing:

The Pre-75 class is supposed to be about the short travel era, rather than the year 1974.
We all know that in the mid 70s, lots of bikes had their shock mounts modified for longer travel. That's absolutely part of MX history, but the idea of the Pre-75 class is to represent the era BEFORE that started happening. This is why GP Maicos, 74 KTMs and YZ-Bs need to have their travel shortened to race in Pre-75 - even though they meet the age cut off.

So I have no issue with the "stock shock locations" rule for Pre-75.

Obviously, for the Evo and newer eras, the need to move shock positions around has disappeared.

Which leaves Pre-78 as the class that needs more thought - this is the era where shock mounts were moved, often. To prohibit that modification now, is historically INaccurate. It's ironic that an original, unmodified-since-it-was-last-raced old race bike doesn't fit anywhere in the VMX rules.

Then again, the rules have been like that for a while - has it actually been a problem for anyone? Or are we discussing a hypothetical that doesn't really exist?

I agree with the 7"and 4" for pre75 Nathan. It wouldn't matter where you put the shocks anyway, unless you wanted to jack up the rear of the bike for sharper steering.

I am interested in the Pre78 rules though. As you say, to prohibit shock mount modification is historically inaccurate. And if someone wants to modify a 75, 76, or 77 model bike so that it complies with the 9" rule, great. More bikes out of sheds and onto the start line 8)
Title: Re: Rule re-write.
Post by: TM BILL on February 10, 2014, 09:01:18 am: This would have to be the most positive thread on here in memory :) People working together , sharing thoughts and ideas and remaining civil and open minded .

Only good can come of it and hopefully more people take the time to read it and add their input .
Title: Re: Rule re-write.
Post by: Michael Moore on February 10, 2014, 09:48:21 am: Quote
This is why GP Maicos, 74 KTMs and YZ-Bs need to have their travel shortened to race in Pre-75 - even though they meet the age cut off.

Isn't the amount of travel the important factor here?

If someone buys a 1973 CZ that had the shocks moved up at some point, requiring mods to both the subframe and swing arm, and they want to race it in the proper 4" rear travel class, why exclude them until such time as they find another bike/pay someone for extensive "return to stock" de-modifications? The bike is period-legal. Let them put on short-travel dampers and run, as long as the wheel doesn't move more than 4".

I've seen bikes like that CZ at AHRMA races. The scrutineers will check the wheel travel and if it 4" or less, "have fun in your pre-75 race, next in line please".

If you are allowing the Maico, AJS etc to run in pre-75 with "moved up by OEM" mounts but with travel-limited dampers then extend the same consideration to all the DIY modified bikes too.

You get another period bike out there and another happy racer who has no competitive advantage over the guy on the stock bike next to him.

cheers,
Michael
Title: Re: Rule re-write.
Post by: firko on February 10, 2014, 09:48:37 am: Quote
The Pre-75 class is supposed to be about the short travel era, rather than the year 1974.
We all know that in the mid 70s, lots of bikes had their shock mounts modified for longer travel. That's absolutely part of MX history, but the idea of the Pre-75 class is to represent the era BEFORE that started happening. This is why GP Maicos, 74 KTMs and YZ-Bs need to have their travel shortened to race in Pre-75 - even though they meet the age cut off.

So I have no issue with the "stock shock locations" rule for Pre-75.

Obviously, for the Evo and newer eras, the need to move shock positions around has disappeared.

Which leaves Pre-78 as the class that needs more thought - this is the era where shock mounts were moved, often. To prohibit that modification now, is historically INaccurate. It's ironic that an original, unmodified-since-it-was-last-raced old race bike doesn't fit anywhere in the VMX rules.

Then again, the rules have been like that for a while - has it actually been a problem for anyone? Or are we discussing a hypothetical that doesn't really exist?

I totally agree with the stock mount stipulation for pre '75 and older classes but I don't think it's relevant for pre 78 because of the reasons Nathan stated. Many racers in that period were riding suspension upgraded pre 75 bikes and, because the pre 78 era was still one of rapid frame development and experimentation, all sorts of set-ups were being tried. As an example, Wayne Morris a bloke in my club was experimenting with Citroen car suspension components and using cut down external spring Maico forks on the rear of his '75 400 Maico (a la Harley Davidson). How about......Rear suspension mounting points can be modified as long as the 9" (10"???) travel limit is observed.

Quote
This would have to be the most positive thread on here in memory :) People working together , sharing thoughts and ideas and remaining civil and open minded .
Only good can come of it and hopefully more people take the time to read it and add their input .

Hallelujah Bill.....this is five years plus overdue. Ironically, I believe it had to be initiated by somebody who had nothing to do with the original rule development (Drakie, me, DT and others) It's a fresh approach, new eyes thing that is sorely needed.
Quote
If you are allowing the Maico, AJS etc to run in pre-75 with "moved up by OEM" mounts but with travel-limited dampers then extend the same consideration to all the DIY modified bikes too
You make a good point Michael but I think that seeing that the pre 75 class has been around for over twenty years and while we saw a number of 'barn find' bikes with modified suspension points turn up in the early days, those guys quickly 'legalised' their bikes to the point that today it's a rare occurrence (if ever) if a pre 75 bike with moved suspension points shows up here in Oz.

More tonight ;D
Title: Re: Rule re-write.
Post by: Nathan S on February 10, 2014, 10:23:24 am: OK, so what if we:
1. Add a clause to the Pre-78 regs that says:
"Machines in the Pre-78 category are exempt from 16.15.7d, and may have the shock absorber mounts moved, providing the total wheel travel does not exceed 9 inches".

And/or

2. Add a clause in the Evo regs that says:
"Machines in the Evo category are exempt from 16.15.7d, but may not alter the number of mounting points".
Title: Re: Rule re-write.
Post by: GMC on February 10, 2014, 10:33:57 am: 2 points I would like to make.

#1 Stay focused
We have had similar discussions over the years but they have always been dragged down with too many opinions on changing this and changing that.
The intent here is to change the wording so the rules will be easier to understand and take out any double meanings and personal interpretations.

Allowing period water cooled heads etc. to pre 78 certainly has its merits but trying to change too much at once will see it all fail.
If your bike isn’t running right you don’t change the carby, jets, ignition and exhaust all in one hit because you will end up chasing your tail.
You work on one thing at a time to eliminate the problems.

#2 Detail actual changes
Trying to read the new version against the old version seems all a bit much to take in easily.
I believe the bureaucracy of MA will want to deal with changing each paragraph line by line.

If you can write it in a way that outlines which rules you’re going to move where and which ones you’re going to rewrite then we will have something that we can all submit to MA

Bagging out MA as them making us adhere to their rules is wrong.
The rules are there for us, they won’t change things for what may seem like a few rebels but if there is unity in the agreement of what needs to be changed then it has more chance of getting passed
Title: Re: Rule re-write.
Post by: supersenior 50 on February 10, 2014, 12:14:05 pm: I am relieved to see this thread is taking a turn from the usual pre nats hysteria and bashing of volunteer officials, towards some rational thought.
We should all be able to understand the spirit of vintage MX and the basic rationale behind the various classes.
Generally rules become more and more complex as more people try to push the envelope and go outside the spiritof it.
I have been in MX for over 50 years as a competitor and office bearer, and 20 years in VMX.
Every Nats Ive been to has had eligibility issues, nearly always brought about by someone pushing the envelope and trying to rewright history for their own agenda. Fortunately the bad old days when personal issues rather than bike issues were sometimes the case, we are lucky with the Commissioners we've had over recent years. Communication direct with Commissioners has surely got to be more productive than rabble rousing on this forum
For all it's perceived faults, in my recent experience I have found the Commission, MQ and MA generally helpfull and supportive in running major events
I have been very heavily involved in organising 2011 CDT, 2012 CMX and 2013 CMX Nationals, and support by officials both paid and volunteer has been excellant.
The drama starts on this forum a month or so leading up to the event, often pre-empting a problem that doesnt exist, or valid issues that should be sorted way earlier.
Come actual scrutineering and it is a storm in a teacup and usually common sence applies. However you can bet that we'll go through it all again next Nats.
The reality is that these issues of forks etc make no differance performance wise to 90% of us punters out there. I could have super duper forks, titanium swing arm and carbon fibre bodywork and bloody Vern would still beat me on his Pre 65 basically standard engined Triumph.
The 10% hot shots in reality dont need, questionable non period parts.
Brad V B is currently arguably the winningest rider in VMX and his bikes are very well prepared, but in the spirit of our sport.
Don't hammer me with specifics, I am talking generally
Title: Re: Rule re-write.
Post by: Nathan S on February 10, 2014, 12:32:55 pm: GMC, you're well on the money as usual/for a change... :P

WRT the line-by-line changes, that mentality is what makes the rules so damn confusing and messy...
The PRC regs that I linked earlier are a classic example of that - the original version wasn't too bad, but they get more wordy and more garbled every year. Those regs are part of my motivation for the tidy up of the CMX regs.

Sometimes the best way to clean your room is to move everything out, and then put back in the bits that are needed.
Title: Re: Rule re-write.
Post by: Mick D on February 10, 2014, 01:35:58 pm: You da man Nathan, great going and diplomacy ;)

I found GMC's post well worth consideration and reading twice, very note worthy.

You can catch more flies with honey, than with vinegar.
Title: Re: Rule re-write.
Post by: GMC on February 10, 2014, 01:37:24 pm: Quote from: Nathan S on February 10, 2014, 12:32:55 pm
WRT the line-by-line changes, that mentality is what makes the rules so damn confusing and messy...

Sometimes the best way to clean your room is to move everything out, and then put back in the bits that are needed.

I totally agree, however I can’t foresee a large bureaucratic organization thinking that way.

If you go to lengths to point out all the current problems and how the complete replacement will work better you might have a chance...
however..
I think you would be best to tackle it rule by rule stating why there is a problem with the rule and how it will improve functionality by moving / replacing the rule.

Glad to be wrong
Title: Re: Rule re-write.
Post by: Nathan S on February 10, 2014, 02:03:57 pm: Correct me if I'm wrong, but I believe that MA's powers-that-be will pretty much rubber-stamp anything that has the support of the relevant commission and the punters.

(Not saying this has either yet, but we seem to be on the right track, at least)
Title: Re: Rule re-write.
Post by: GMC on February 10, 2014, 02:22:38 pm: Correct me if I’m wrong but I believe if enough punters back it then MA will take it seriously.
Then it is up to the commissioners, some of who may not be relevant (classic road race for instance, not too sure on this)

When you think you have all the bugs ironed out then I suggest you run it by the relevant commissioners to get their take on it before it is submitted to MA

If they are all in agreement with it then it has a good chance of being passed.

Once you get to this stage then we can all copy and paste to submit it to MA

If there are lots of people submitting lots of different versions then it will probably fall in a heap.
Title: Re: Rule re-write.
Post by: bazza on February 10, 2014, 02:28:24 pm: When you think you have all the bugs ironed out then I suggest you run it by the relevant commissioners to get their take on it before it is submitted to MA

If they are all in agreement with it then it has a good chance of being passed.

Once you get to this stage then we can all copy and paste to submit it to MA

If there are lots of people submitting lots of different versions then it will probably fall in a heap.

Seems like a good idea
Title: Re: Rule re-write.
Post by: Slakewell on February 10, 2014, 05:23:10 pm: My only whinge is the 9" Pre 78 rule. I still feel that for pre 78 no limit is the best rule. Less rules mean less BS. When most bikes need to be modified to fit the rules then something is wrong. ( Just because the most chosen bike in the class needs no mods doesn't make it right) Having to back engineer CCM's, VB monty's GP Huskies, AW Maico's and the like is just wrong on so many levels. How many times have I read in this thread about how it was back in the day and how we need to reflect that? You tell me how many people back in 77 shorten there suspension? I think you find that's a round figure.
Title: Re: Rule re-write.
Post by: Ted on February 10, 2014, 05:25:54 pm: And all that will do is start Evo from 1/1/1975
Title: Re: Rule re-write.
Post by: Slakewell on February 10, 2014, 05:45:55 pm: Quote from: Ted on February 10, 2014, 05:25:54 pm
And all that will do is start Evo from 1/1/1975

Ted we can never agree on every topic. Keep in mind that their was a good reason that even 77 people didn't modify there bikes to 12" travel. Counter shaft sprocket location. 78/79 saw new crank cases on most bikes so they could increase there travel and keep there chain on.
Title: Re: Rule re-write.
Post by: Ted on February 10, 2014, 05:57:42 pm: Quote from: HeavenVMX on February 10, 2014, 05:45:44 pm
Quote from: Slakewell on February 10, 2014, 05:23:10 pm
My only whinge is the 9" Pre 78 rule. I still feel that for pre 78 no limit is the best rule. Less rules mean less BS. When most bikes need to be modified to fit the rules then something is wrong. ( Just because the most chosen bike in the class needs no mods doesn't make it right) Having to back engineer CCM's, VB monty's GP Huskies, AW Maico's and the like is just wrong on so many levels. How many times have I read in this thread about how it was back in the day and how we need to reflect that? You tell me how many people back in 77 shorten there suspension? I think you find that's a round figure.

I agree that the 9" rule requires several bikes to reduce travel by about 1" but without that rule owners of '75 & '76 models may as well scrape them. I have a VB360 which has had 1.25" taken out of the suspension front and back it is still competative. We are not racing exactly as we did in 1977 we are racing to represent an era. Otherwise why allow modern shocks, modern carbies in Pre65 and the list would go on and on.

As much as it effing well shocks and disturbs me to my last mortal cell I have to agree with Ted on this one. You do not realise how much that pains me to say :P :P ;D

Well you really are wiser than first thought ;D

So answer my question from the other day. What is Heavens stance on Evo. Same old same old ( which is great ) or open slather Tanner twin shock rules. I have the lathe running and waiting your response.

BTW I will bring that B pipe up for you at first meeting. Not sure it will get your bike to the finish line but your bike will look better being pushed back to camp 8) I've also got heaps of spokes if ya want them........free for mates ;D
Title: Re: Rule re-write.
Post by: DJRacing on February 10, 2014, 07:42:27 pm: Evolution class bikes must have been manufactured with Non Linkage suspension and Drum-brakes and Aircooled motors.
All parts from those bikes are permissible as are all after-market parts of this era.
a) Modifying your bike with other major parts from a newer era is not allowed.

These words mean you can have period correct "works" parts and period correct after-market parts like, water-cooling and all the other hot bling items from that era. It also means that you can't use parts from a Pre85 era bike or newer if it's a major part which are already defined in the rules.
This I believe show cases the era or period of what we call Evo VMX with its long travel suspension and also what hop-up/after-market parts were available at the time.
Title: Re: Rule re-write.
Post by: Mick D on February 10, 2014, 07:44:31 pm: Quote from: DJRacing on February 10, 2014, 07:42:27 pm
Evolution class bikes must have been manufactured with Non Linkage suspension and Drum-brakes and Aircooled motors.
All parts from those bikes are permissible as are all after-market parts of this era.
a) Modifying your bike with other major parts from a newer era is not allowed.

These words mean you can have period correct "works" parts and period correct after-market parts like, water-cooling and all the other hot bling items from that era. It also means that you can't use parts from a Pre85 era bike or newer if it's a major part which are already defined in the rules.
This I believe show cases the era or period of what we call Evo VMX with its long travel suspension and also what hop-up/after-market parts were available at the time.

Very nice
Title: Re: Rule re-write.
Post by: micks on February 10, 2014, 08:56:38 pm: very very good that simple but again to be period correct you need a period and then you can have a newer era
Title: Re: Rule re-write.
Post by: FourstrokeForever on February 10, 2014, 09:12:31 pm: "A further area that possibly needs consideration is the requirement to have shock mounts in there original position. If a bike meets the suspension requirments does it matter? certainly back in the day people did all sorts of things. Maybe it should apply to Pre75 and earlier only?"

That is exactly what Nathans re-write of the rules is proposed. Yes, suspension travel limits are required otherwise we will end up with all sorts of frankenstien beasts that do not represent any specific era. In most cases, the bike with increased travel will be unrideable anyway. Imagine a 1974 CR250 with 8"s of suspension travel at the back.....YUK.

Quote from: GMC on February 10, 2014, 02:22:38 pm
Correct me if I’m wrong but I believe if enough punters back it then MA will take it seriously.
Then it is up to the commissioners, some of who may not be relevant (classic road race for instance, not too sure on this)

When you think you have all the bugs ironed out then I suggest you run it by the relevant commissioners to get their take on it before it is submitted to MA

If they are all in agreement with it then it has a good chance of being passed.

Once you get to this stage then we can all copy and paste to submit it to MA

If there are lots of people submitting lots of different versions then it will probably fall in a heap.

Exactly right Geoff. The proposed rules need to fit in with what the MAJORITY of riders want as their new bible. I'm sure that Nathan's intent is to give the punters what they deem as the way forward. Sure, there will no doubt be the odd detractor, but that's the way of a democratic society. If the majority agree that the final, and we're not there yet, set of proposed rules are the way of the future, then yes, copy and paste a submission. That can not fail. The strength is in numbers, as it has always been in everything beaurocratic with democracy at it's heart apart from those that CONTROL motorsport in this country. United we stand, divided nothing will be gained. I don't think the classic road race committee should have anything to do with CMX or PCMX or have any right to vote on what the Classic MX committee want to do. And I'm sure they wouldn't want any interference from the Classic MX committee either. They are both entirely different classes of motorcycle sport.
Title: Re: Rule re-write.
Post by: Rossvickicampbell on February 10, 2014, 09:24:10 pm: I have previously - and still do - agree with Mr Slakewell on the suspension travel limits - and have to ask why this area gets picked out as being limited to fall into an era when the bike resides. yes I have a YZB - it is pre 75 but it is bought back to the field because it was ahead of everybody else - why? It seems to impact more on pre-78 than pre 75 but as mentioned eras are used to sort groups and if a particular bike falls into that category why penalise it. Surely there is enough knowledge around that we could leave the statement that suspension must not exceed OEM specs or similar or the maximum for a particular bike in an era Ie pre 75 could be maxed out at whatever the YZB was??

I see previously lots of comments about this - particularly with pre 78 yet seems the normal commentators on this are absent currently?
Title: Re: Rule re-write.
Post by: DJRacing on February 10, 2014, 09:29:30 pm: Quote from: micks on February 10, 2014, 08:56:38 pm
very very good that simple but again to be period correct you need a period and then you can have a newer era

Nathan has already put an era in for Evo. 1982
There already is an era or period with those rules because basically there were no more improvements to a bike built with Non Linkage and Drum-brakes and Aircooled motor.
Title: Re: Rule re-write.
Post by: FourstrokeForever on February 10, 2014, 09:34:32 pm: Quote from: Rossvickicampbell on February 10, 2014, 09:24:10 pm
I have previously - and still do - agree with Mr Slakewell on the suspension travel limits - and have to ask why this area gets picked out as being limited to fall into an era when the bike resides. yes I have a YZB - it is pre 75 but it is bought back to the field because it was ahead of everybody else - why? It seems to impact more on pre-78 than pre 75 but as mentioned eras are used to sort groups and if a particular bike falls into that category why penalise it. Surely there is enough knowledge around that we could leave the statement that suspension must not exceed OEM specs or similar or the maximum for a particular bike in an era Ie pre 75 could be maxed out at whatever the YZB was??

I see previously lots of comments about this - particularly with pre 78 yet seems the normal commentators on this are absent currently?

I do agree Ross. If a certain model bike had more suspension travel as standard before December 31/1974, then I don't think it should be restricted to suit the 7" and 4" rule. It is actually backward engineering the original bike. Maybe there should be some exceptions to the rule rather than allowing all pre75 machines to have 5" rear suspension travel....
Title: Re: Rule re-write.
Post by: VMX247 on February 10, 2014, 09:39:13 pm: Quote from: Lozza on February 09, 2014, 10:34:06 pm
Quote from: Nathan S on February 09, 2014, 07:25:19 pm
Quote from: Lozza on February 09, 2014, 06:51:37 pm
I would 16.15.7.(ba) to "operationaly similar and visualy indistinguishable" other than that pretty much complete
Why?
Indistiguishable is clear and defined , 'similar' is open to interpretation. Similar operation means things like I could not convert a powervalve to servo operation from governed off the crank. here is an example

x2 more
Title: Re: Rule re-write.
Post by: Lozza on February 10, 2014, 09:40:58 pm: Quote from: Rossvickicampbell on February 10, 2014, 09:24:10 pm
I have previously - and still do - agree with Mr Slakewell on the suspension travel limits - and have to ask why this area gets picked out as being limited to fall into an era when the bike resides. yes I have a YZB - it is pre 75 but it is bought back to the field because it was ahead of everybody else - why? It seems to impact more on pre-78 than pre 75 but as mentioned eras are used to sort groups and if a particular bike falls into that category why penalise it. Surely there is enough knowledge around that we could leave the statement that suspension must not exceed OEM specs or similar or the maximum for a particular bike in an era Ie pre 75 could be maxed out at whatever the YZB was??

I see previously lots of comments about this - particularly with pre 78 yet seems the normal commentators on this are absent currently?

Suppose it saves grumbles from everyone when you smoke the field at the Nats Rossco :D
Title: Re: Rule re-write.
Post by: Nathan S on February 10, 2014, 10:45:18 pm: Quote from: Rossvickicampbell on February 10, 2014, 09:24:10 pm
I have previously - and still do - agree with Mr Slakewell on the suspension travel limits - and have to ask why this area gets picked out as being limited to fall into an era when the bike resides. yes I have a YZB - it is pre 75 but it is bought back to the field because it was ahead of everybody else - why? It seems to impact more on pre-78 than pre 75 but as mentioned eras are used to sort groups and if a particular bike falls into that category why penalise it. Surely there is enough knowledge around that we could leave the statement that suspension must not exceed OEM specs or similar or the maximum for a particular bike in an era Ie pre 75 could be maxed out at whatever the YZB was??

I see previously lots of comments about this - particularly with pre 78 yet seems the normal commentators on this are absent currently?

The idea is that Pre-75 is for bikes with short travel suspension, and the year of manufacture is a secondary concern. It's not about the year 1974, its about the short travel era.

Your bike is an oddity, in that it was one of two/three 'production' bikes with more than 4" of rear travel - in some ways, I'd say that it's proper home is the Pre-78 class, being the "transition era"... The existing rules prohibit you from entering your 1974 model bike in Pre-78, though...
The proposed rules give you the choice of limiting the rear travel and racing with the short travel bikes, or leaving it in original spec and racing Pre-78.
Title: Re: Rule re-write.
Post by: firko on February 10, 2014, 10:47:32 pm: Here's some quick ideas and suggestions. As I said earlier I'm a bit tapped for time for various reasons so once I've closely read everyone elses contributions I'll hoprfully make some more additions or changes. My comments are in red (Nathans in blue)

16.15.7 Acceptable machines and components”

I believe that there are some problems with people understanding the legality of aftermarket alloy swingarms and billet triple clamps in pre 75 (and possibly other classes). It's my understanding that the only alloy swingarms available prior to 1975 were Boyd and Stellings and derivatives of their design using the same manufacturing principles, and OSSA Phantom swingarms. The generic Landrus rstyle swingarm and Thor style extruded swingarms should not be allowed in pre 75.

I have yet to see any legitimate proof of billet alloy triple clamps being available prior to 1975. Profab cast aluminium and magnesium triple clamps should be allowed along with modern billet
replicas of them. I think that the swingarm and triple clamp situation should be clearly spelled out in the MoMs as both swingarms and triple clamps are deemed to be 'Major components'

b) Any major component that is visually similar and operationally indistinguishable from the original will be accepted regardless of the date of manufacture. ( I am not happy with "similar" - the word "identical" is too strict for minor differences like casting changes, but "similar" is too vague. Open to input on that one! I agree....how about must be 'visually comparable'?

c) Any modifications to major components must be using principles and techniques that were available in the era the machine is entered in. (just stops loop-holing tactics) This is a difficult rule to enforce. How would one define “principles and techniques”? I don't understand “loop holing”.
How about...All major modifications must be sympathetic with accepted period modifications. Dated period photographic evidence (magazine etc) may be needed for legal verification. (I know it's ambiguous and wordy but I think we need to show historic precedent.

(I killed "exhaust must follow original lines" because it achieves nothing.

I Absolutely agree. This rule contradicted period fitting of up pipes to bikes originally fitted with down pipes and visa versa.

Pre 60 Solo. This class is intended to represent the formative era of motocross. (Weakly worded - needs input from the old hands). This class is intended to represent the era of motocross prior to the emergence of purpose built machines.

Pre 65 Solo. This class is intended to represent the first generation of purpose-built motocross bikes. (Again, weakly worded pre-amble - input please) This division represents the first generation of purpose built motocross machines

Pre 70 solo. This class is intended to represent the era where 4-stroke machines lost their dominance and 2-stroke machines became dominant. This division represents to emergence of two strokes dominance of motocross.

16.15.9.10Acceptable follow on models: AJS Stormer 250; Greeves griffon models; Yamaha AT1, CT1, RT1 without reed valve induction. (tightening up the wording slightly) There are a lot of post 1970 machines that could be included as flow ons.....serious research needed here.

Pre 75 Solo. This class is intended to represent the last of the short travel suspension era This division represents the last short suspension era and motocross's first boom. \
Acceptable follow on models pre 75: ]As in pre 70 and other divisions, a definitive flow on list needs to be reseached.

Pre 78 Solo and Women's Pre-78. This class is intended to represent the transition era between the short travel Pre-75 machines and the long travel Evo machines. Perfect, although I think the womens division should be in a separate section. As in the previous divisions, serious research is needed to compile an accurate flow on list.

16.15.11.2 Front wheel travel will not exceed 229mm (9 inches) rear wheel travel will be limited to 229mm (9 inches) measured at the axle. (I want to change this to 10", but in the spirit of not changing the regs, I have resisted...) I agree with the change to 10” but also agree that it needs a separate discussion at another time.

Evolution. This class is intended to represent the era of long suspension travel, before water-cooling, disc brakes and linkage rear suspension became dominant.
I don't believe that the Evolution class represents a particular era. Perhaps this is more in keeping of the concept.......”The Evolution division is a technology oriented class for machines with air cooling, drum brakes and non linkaged suspension”.

Because I'm not involved with or up to speed on the eligibility criteria of any post Evo classes I have deliberately stayed away from contributing any thoughts or ideas.
Title: Re: Rule re-write.
Post by: firko on February 10, 2014, 11:08:56 pm: Quote
Your bike is an oddity, in that it was one of two/three 'production' bikes with more than 4" of rear travel - in some ways, I'd say that it's proper home is the Pre-78 class, being the "transition era"... The existing rules prohibit you from entering your 1974 model bike in Pre-78, though...
For what it's worth in this discussion, the following bikes had more than 4" of rear travel in 1974...
Maico, KTM, Yamaha YZ/B, CCM, AJS Stormer, Kramer and (anecdotally, and if so, ever so slightly) Husqvarna and Montesa.
Title: Re: Rule re-write.
Post by: FourstrokeForever on February 11, 2014, 08:18:38 am: Quote from: firko on February 10, 2014, 11:08:56 pm
Quote
Your bike is an oddity, in that it was one of two/three 'production' bikes with more than 4" of rear travel - in some ways, I'd say that it's proper home is the Pre-78 class, being the "transition era"... The existing rules prohibit you from entering your 1974 model bike in Pre-78, though...
For what it's worth in this discussion, the following bikes had more than 4" of rear travel in 1974...
Maico, KTM, Yamaha YZ/B, CCM, AJS Stormer, Kramer and (anecdotally, and if so, ever so slightly) Husqvarna and Montesa.

I still think that those mentioned bikes that were produced with more than 4" of rear travel should be accepted as eligible for pre75 with their original rear travel without forcing people to modify their bike(s) to have less travel. At the end of the day, 1" more travel isn't going to make a great deal of difference IF, and only IF, the bike was manufactured that way.
Title: Re: Rule re-write.
Post by: yamaico on February 11, 2014, 09:01:38 am: Quote from: TBM on February 10, 2014, 09:34:32 pm
Quote from: Rossvickicampbell on February 10, 2014, 09:24:10 pm
I have previously - and still do - agree with Mr Slakewell on the suspension travel limits - and have to ask why this area gets picked out as being limited to fall into an era when the bike resides. yes I have a YZB - it is pre 75 but it is bought back to the field because it was ahead of everybody else - why? It seems to impact more on pre-78 than pre 75 but as mentioned eras are used to sort groups and if a particular bike falls into that category why penalise it. Surely there is enough knowledge around that we could leave the statement that suspension must not exceed OEM specs or similar or the maximum for a particular bike in an era Ie pre 75 could be maxed out at whatever the YZB was??

I see previously lots of comments about this - particularly with pre 78 yet seems the normal commentators on this are absent currently?

I do agree Ross. If a certain model bike had more suspension travel as standard before December 31/1974, then I don't think it should be restricted to suit the 7" and 4" rule. It is actually backward engineering the original bike. Maybe there should be some exceptions to the rule rather than allowing all pre75 machines to have 5" rear suspension travel....

This will open the floodgates for LTR conversions on every radial Maico.
Title: Re: Rule re-write.
Post by: GMC on February 11, 2014, 09:20:59 am: Focus guys, focus.

I’m normally in favour of thread hijacks but talking about travel restrictions or any other rule deviation will just bog this thread down with a heap of crap again.

The purpose here is to improve the wording which people have been complaining about for decades and I believe if too many changes are added in the same proposal then the whole lot will be thrown out the window.

If you want to debate water cooling in Evo or 10” travel for pre 75 then start another thread.
Title: Re: Rule re-write.
Post by: firko on February 11, 2014, 09:45:32 am: Quote
Focus guys, focus.
I’m normally in favour of thread hijacks but talking about travel restrictions or any other rule deviation will just bog this thread down with a heap of crap again.
The purpose here is to improve the wording which people have been complaining about for decades and I believe if too many changes are added in the same proposal then the whole lot will be thrown out the window.
If you want to debate water cooling in Evo or 10” travel for pre 75 then start another thread
I agree Geoff, Nathans already stated that it's not the intention of the thread to change the rules, only to make the wording more user friendly. I only made my list in reference to a previous post and to let folks know that it's not just the Yamaha and Maico that have more travel.
Title: Re: Rule re-write.
Post by: FourstrokeForever on February 11, 2014, 10:11:00 am: Quote from: firko on February 11, 2014, 09:45:32 am
Quote
Focus guys, focus.
I’m normally in favour of thread hijacks but talking about travel restrictions or any other rule deviation will just bog this thread down with a heap of crap again.
The purpose here is to improve the wording which people have been complaining about for decades and I believe if too many changes are added in the same proposal then the whole lot will be thrown out the window.
If you want to debate water cooling in Evo or 10” travel for pre 75 then start another thread
I agree Geoff, Nathans already stated that it's not the intention of the thread to change the rules, only to make the wording more user friendly. I only made my list in reference to a previous post and to let folks know that it's not just the Yamaha and Maico that have more travel.

Fair enough statements guys. I was just thinking of adding something along the lines of some exceptions to the pre75 7 and 4 rule for bikes that came standard with a bit more travel. Afterall, they raced back in the day with their original configuration without restriction.
Title: Re: Rule re-write.
Post by: firko on February 11, 2014, 11:39:34 am: I think we're now well on the way to sorting the MoMs wording and interpretation out. From what I can see there are some classes that need little or no modifications to their wording or rules. One problem that is appearing more and more however is the use of trick 'billet' or custom made aftermarket parts manufactured in the USA and elsewhere. Many people seem to think that if a part is allowed in AHRMA competition it must automatically be allowed here. At the risk of repeating my point, alloy billet triple clamps might well be legal for pre 75 in AHRMA competition but they are not legal under our MoMs. This is also seen in the number of KLR or Thor style swingarms appearing on Australian pre 75 bikes, their riders assuming them to be legal when in fact they aren't according to the MoMs definition of 'Major Component' and period integrity.
*Pre 75 has traditionally been the sports most popular class and needs nothing other than some minor wording changes and parts eligibility criteria detail added (eligible aftermarket 'Major Components' (aftermarket frames, swingarms and triple clamps, see Reply #93 ).

*Pre 78 seems to be the class most in need of a definition tune up. The rules for the class were originally 'borrowed' almost to the word from the AHRMA rule book and it's since shown that they hold some inherent flaws . The biggest problem seems to be in suspension limits, many racers believing that the current 9" limit is inadequate. I believe that the suspension limit needs to be adjusted to that of the longest OEM travel bike in the class, whether that be 10", 11" or whatever. It's easier to put an inch of travel into a bike than to de-engineer it to a lower limit (9"). Another situation that seems to be worth investigating is to remove the "standard suspension mounting points" stipulation. Once again, harking to my earlier post, there wasn't another era except maybe for pre 65 where bikes were modified more for increased performance. The suspension revolution was in full swing in the '75-'78, with all sorts of frame and swingarm mods being commonplace. A lot of guys were still racing their '74 (and earlier) bikes with upgraded suspension mods, I myself had a Montesa 360 with Maico style rear suspension and Marzocchi forks.
I'd suggest removing any reference to suspension mounting points from the pre '78 regs.

Evolution. DJ's on the money with his ideas (Reply #82 ). The beauty of Evo is in its simplicity and lack of overbearing eligibility rules, it's the poster child for the KISS principle. For that reason lets not over complicate it with too many words. Here's my version....
*Evolution class machines must be air cooled, have drum brakes and non linkaged suspension.
*All major components must have been derived from an air cooled, drum braked and non linkaged motorcycle.
*Parts from any bike that is water cooled, disc braked or featuring linkaged suspension are not allowed.
* There are no suspension travel limits in Evolution.

Another challenge is to create a fair eligibility list for pre '60 and pre '65. These classes are undergoing a small but inspiring resurgence in interest and I feel that to make the classes as accessible as possible we need to broaden their eligibility criteria. I make reference to the BSA B40 distributor/points models grey area for pre 65 and acceptance of modern Indian manufactured Royal Enfields as a cheap and readily available machine for both pre '60 and/or pre 65 as examples of some points that need to be addressed. There needs to be a serious discussion and research into allowing as many machines into both classes without infecting the historic integrity of the class(es).

A similar research undertaking is needed to compile a list of eligible flow on models for all classes with the exception of Evo. There are already some listed flow ons for pre 70 and pre 75 but I feel that there are more machines that could be allowed for those classes and that a similar list be created for pre '78, pre 85 and pre 90. I propose that volunteer committees of knowledgeable people should be formed to consider flow on alternatives for all eras. There are some very knowledgeable and passionate people (many of them frequenting this forum) interested in the various divisions that I feel could really make a contribution.
Title: Re: Rule re-write.
Post by: sa63 on February 11, 2014, 02:55:37 pm: where do (newly made) EVO shocks with clickers fit into the above proposals - surely these are as major a component as forks?
There aren't enough old shocks left to use.. and improved parts are now made ,so the wording should also incorporate newly made items rather than a flat statement about the origin of the part being from a non linkage bike.
But then I agree with DTs statement about any original drum brake front end being ok, especially as new shocks are way more sophisticated than any pre85 drum brake front end..
Title: Re: Rule re-write.
Post by: firko on February 11, 2014, 03:20:03 pm: Shocks aren't regarded as major components mainly because they are an often replaced item. There are arguments for and against external clickers being allowed in some classes, especially pre 75 but it's been proven beyond doubt that stacked shim shocks with external dampening adjustment existed in 1973. The fork situation raised by DT isn't in essence a bad idea, it's more the timing of his announcement that any drum braked front end can be used being so close to the Nats that causes the controversy.
Title: Re: Rule re-write.
Post by: Brian Watson on February 11, 2014, 04:11:56 pm: The biggest problem seems to be in suspension limits, many racers believing that the current 9" limit is inadequate. I believe that the suspension limit needs to be adjusted to that of the longest OEM travel bike in the class, whether that be 10", 11" or whatever. It's easier to put an inch of travel into a bike than to de-engineer it to a lower limit (9"). ..........From post #100..I would have trouble with this.. to re-engineer a set of forks that had 9 in of travel to 11 in (or whatever travel is the longest) is asking for trouble..the amount of overlap in a 9 in set of forks would not (safely) allow you to extent the travel to 11 in.. much, much easier to reduce the travel than to add some in.. to reduce all you need to do is to add a spacer or add a longer rebound spring onto the damper rod.... to add travel you need to extend the damper rod....
Title: Re: Rule re-write.
Post by: firko on February 11, 2014, 04:24:15 pm: True, I wasn't thinking of modifying damper rods, I was thinking more along the lines of changing the forks as a unit. Point taken though.
Title: Re: Rule re-write.
Post by: Ted on February 11, 2014, 06:20:24 pm: Mark, where are you getting your suspension theories from

1- Where do you get a pair of 36 mm forks manufactured before 1/1/78 from that will allow eleven inches of travel

2- The amount of flex alone with that much travel would be bordering on dangerous.

3- It is far cheaper and easier to reduce travel than increase it

I suggest you take a pair of shocks to a suspension guy and get a quote on putting a two inch increase into them and then get a quote on reducing them by the same margin. You will change your view then

Quote from: Watto HVA 1 on February 11, 2014, 04:11:56 pm
The biggest problem seems to be in suspension limits, many racers believing that the current 9" limit is inadequate. I believe that the suspension limit needs to be adjusted to that of the longest OEM travel bike in the class, whether that be 10", 11" or whatever. It's easier to put an inch of travel into a bike than to de-engineer it to a lower limit (9"). ..........From post #100..I would have trouble with this.. to re-engineer a set of forks that had 9 in of travel to 11 in (or whatever travel is the longest) is asking for trouble..the amount of overlap in a 9 in set of forks would not (safely) allow you to extent the travel to 11 in.. much, much easier to reduce the travel than to add some in.. to reduce all you need to do is to add a spacer or add a longer rebound spring onto the damper rod.... to add travel you need to extend the damper rod....

To get 50 mm more travel out of Pre 78 forks you would have to use longer staunchions as well as longer sliders, say off a T model. Which is illegal.

The 9 inch rule was in long before these guys with 11 inch travel started racing VMX. They were well aware of the limit. Do what Scrivo did, change it to nine inches. He's not complaining.
Title: Re: Rule re-write.
Post by: Rossvickicampbell on February 11, 2014, 07:18:19 pm: Teed - that is incorrect isn't it - travel longer than 9 inches - be it whatever it is - was certainly in for pre-78 - hence the questions being asked about the limitation?
Title: Re: Rule re-write.
Post by: Ted on February 11, 2014, 07:45:25 pm: All right, then you answer the question then. Where are you going to get forks from that will have 11 inches travel in 35, 36 mm diameter manufactured before 1/1/1978

Every one is up in arms now because they can't buy Evo legal H forks and TLS hubs. How many 35 / 36 mm forks are out there with 11 inches of travel. You can say 250 and open have 38 mm forks, but if you make it 11 inches for Pre 78 you have to include all capacities.

A good brand, well set up shock at 9 inches will easily out perform a cheap shit shock at what ever length you care to make it.

To be quite honest I hope it comes in, everybody has 11 inches in Pre 78. I for one will be leaving mine at 9 inches. It's not rocket science why 8)
Title: Re: Rule re-write.
Post by: mick25 on February 11, 2014, 09:21:49 pm: Quote from: Ted on February 11, 2014, 07:45:25 pm
All right, then you answer the question then. Where are you going to get forks from that will have 11 inches travel in 35, 36 mm diameter manufactured before 1/1/1978

Every one is up in arms now because they can't buy Evo legal H forks and TLS hubs. How many 35 / 36 mm forks are out there with 11 inches of travel. You can say 250 and open have 38 mm forks, but if you make it 11 inches for Pre 78 you have to include all capacities.

A good brand, well set up shock at 9 inches will easily out perform a cheap shit shock at what ever length you care to make it.

To be quite honest I hope it comes in, everybody has 11 inches in Pre 78. I for one will be leaving mine at 9 inches. It's not rocket science why 8)
;) and better corner speed with the nine inch travel , less raked out front 8)
Title: Re: Rule re-write.
Post by: Ted on February 11, 2014, 09:41:30 pm: Shhhhh......Michael
Title: Re: Rule re-write.
Post by: firko on February 11, 2014, 09:42:26 pm: Ted, read what I said again......I said make the travel maximum limit whatever is the OEM maximum length for the pre 78. If you read my answer to Watto's post (which you obviously hadn't) you'd see that I took the theory that if people wanted that travel (whatever it be) the option is there for them to fit those forks or aftermarket forks to meet that travel limit. I hadn't considered increasing the travel of those forks because I knew it was not a feasible modification. Funny that two sentences in my lengthy post in my lengthy post aroused such a reaction yet there's not a word of opinion about any of the other stuff. I personally don't give a fluck. I made that point to keep those with 11 of travel happy and not have to de engineer their bikes. Everyone else can keep theirs stock or increase it to 11" their call................afterthought..... I personally think 10" is a good compromise but let's not turn this into another swingarm debate. This thread isn't about changing the rules so it stays 9" anyway. It's all hypothetical bullshit.
Title: Re: Rule re-write.
Post by: JohnnyO on February 11, 2014, 09:46:24 pm: You can't safely get 11" out of pre 78 forks, they will have such little overlap they'll fold in half over a decent jump and have so much flex they'll be dangerous.
Much the same with the rear, any more than 10" and you'll have a ridiculous swingarm angle and a never ending problem of throwing or breaking chains and smashing engine cases because the countershaft sprocket on pre 78 bikes is too far from the swingarm pivot.
Title: Re: Rule re-write.
Post by: Ted on February 11, 2014, 09:52:32 pm: My point exactly John

You will also have to pick six ruts to corner in because the flex will start you in one and end you in six.
Title: Re: Rule re-write.
Post by: firko on February 11, 2014, 09:53:21 pm: Quote
I believe that the suspension limit needs to be adjusted to that of the longest OEM travel bike in the class, whether that be 10", 11" or whatever
I agree with all of you.....If you'd have read the above sentence you'd have realised that I wasn't sure what the longest travel bike was in 1977...hence the or whatever clause. I've said earlier that I think 10" is a fair limit, I only mentioned 11" because I seemed to recall Slakey or someone stating that a particular bike had 11" of travel. Fluck me, talk about selective interpretation ::).
Title: Re: Rule re-write.
Post by: Ted on February 11, 2014, 09:53:59 pm: Also John, nobody has answered where do we get these mythical Pre 78 11 inch forks and stanchions from
Title: Re: Rule re-write.
Post by: Ted on February 11, 2014, 09:59:35 pm: Mark, How many racers believe 9 inches travel in Pre 78 is inadequate 1,2 or 3
Title: Re: Rule re-write.
Post by: mick25 on February 11, 2014, 10:00:45 pm: Quote from: Ted on February 11, 2014, 09:53:59 pm
Also John, nobody has answered where do we get these mythical Pre 78 11 inch forks and stanchions from
They must be removing the small return spring in the forks ted to make the damper rod longer to gain 1 and half inches more travel ;D
Title: Re: Rule re-write.
Post by: Ted on February 11, 2014, 10:02:48 pm: Am sanding all day tomorrow. Wanna come ;D
Title: Re: Rule re-write.
Post by: mick25 on February 11, 2014, 10:07:34 pm: Quote from: Ted on February 11, 2014, 10:02:48 pm
Am sanding all day tomorrow. Wanna come ;D
Hell yeah ??? love the sanding at summer time :o I hope its all square sett no cove :P whats the pay any gifts , RM swing arm ;D
Title: Re: Rule re-write.
Post by: firko on February 11, 2014, 10:09:23 pm: Quote
Am sanding all day tomorrow. Wanna come
I thought you were going on a cruise with Simo Ted?
Can we get back on the subject? This thread's got nothing to do with suspension travel in pre 78. I'm sorry I mentioned it. :(
Title: Re: Rule re-write.
Post by: Ted on February 11, 2014, 10:15:37 pm: Quote from: firko on February 11, 2014, 10:09:23 pm
Quote
Am sanding all day tomorrow. Wanna come
I thought you were going on a cruise with Simo Ted?
Can we get back on the subject? This thread's got nothing to do with suspension travel in pre 78. I'm sorry I mentioned it. :(

I'm flying in tomorrow ;D
Title: Re: Rule re-write.
Post by: Davey Crocket on February 11, 2014, 11:17:04 pm: Like GMC say's, if you make too many changes at once then it will end up as toilet paper....I would leave the 9 inches alone....it's worked great for 15 years or so, the majority of riders are happy with it, just like pre75 and earlier has 7 and 4, it's right...separates the classes into distinctive era's.
Title: Re: Rule re-write.
Post by: Michael Moore on February 12, 2014, 03:46:29 am: In re dampers with external adjusters, Koni came out with them in steel (model 8211) during the 1960s. The aluminum 8212 was introduced in 1967. Those were for race cars but the technology was there for anyone to buy and copy.

cheers,
Michael
Title: Re: Rule re-write.
Post by: Michael Moore on February 12, 2014, 08:06:54 am: Quote from: firko on February 10, 2014, 10:47:32 pm
I believe that there are some problems with people understanding the legality of aftermarket alloy swingarms and billet triple clamps in pre 75 (and possibly other classes). <snip>

I have yet to see any legitimate proof of billet alloy triple clamps being available prior to 1975. Profab cast aluminium and magnesium triple clamps should be allowed along with modern billet replicas of them. I think that the swingarm and triple clamp situation should be clearly spelled out in the MoMs as both swingarms and triple clamps are deemed to be 'Major components'

I just pulled out my copy of Terry Pratt's "Grand Prix Motocross - the 1972 World Championship Season" and on page 102 there's a photo of a works CZ lower clamp with the caption:

Quote
Some of the CZ Grand Prix bikes are equipped with this special lower yoke. It offers much greater gripping surface against the fork tube and has two pinch bolts on each side. While the production single bolt yoke is made from an aluminum casting, these works parts appear to be machined from solid stock

If someone wanted a different clamp before the next race it is a lot easier to grab a slab of aluminum, bore 3 accurate holes and then the rest could be finished with a band saw, drill press and belt sander (or a dreadnought file) compared to making a pattern, having it cast, having the raw casting heat treated, and then doing the accurate boring and drilling/tapping operations.

Husqvarna and Rob North (among others) had fabricated steel clamps in the period so there's three different methods of making them -- fabrication/welding, machining and casting (which also requires machining).

Looking at some 1970s Maico single-bolt clamps I'm not seeing much to distinguish this cast part from a similar clamp machined from solid. They are just a flat plate, no fancy contours or droops to them. Casting makes sense when you are doing mass production.

I've got early/mid 1970s Betor and Yamaha 35mm clamps that have two pinch bolts at each point so that is clearly a period feature.

Mark, it looks to me like the problem some people have with "billet" clamps is not that they are machined from solid but rather that some of them look like they are from a much later period than pre-1975. That seems to be a no different problem from running a fat snail expansion chamber exhaust suitable for a 1995 bike on a pre-1975 bike. The problem isn't that a welded steel chamber is out of period, it is that the design is out of period.

Rather than exclude a period manufacturing technique why not apply a "must look period" test?

cheers,
Michael
Title: Re: Rule re-write.
Post by: FourstrokeForever on February 12, 2014, 08:41:04 am: Quote from: firko on February 11, 2014, 10:09:23 pm
Quote
Am sanding all day tomorrow. Wanna come
I thought you were going on a cruise with Simo Ted?
Can we get back on the subject? This thread's got nothing to do with suspension travel in pre 78. I'm sorry I mentioned it. :(

There's always a few who want to argue about the most minute detail that has nothing to do with what was actually written Mark..... No wonder there is a need for a re-write of the MOMs when you can read the amount of reading between the lines that goes on here. Everything has to be spelt out in black and white, with no shades of grey.

For a start, Pre78 are allowed to run 38mm forks at the moment. It should stay that way.

Suspension travel is limited to 9" front and rear. It should stay that way.

Perhaps the shock mounting points rule could be removed altogether or altered to allow modification. Again, the rear wheel travel MUST remain at or less than 9".

As for Evolution, I think DT's brave decision to allow any drum brake front fork is a good one. Perhaps not for this year because of the confusion (by some) created by announcing it so close to this years Nats. But at the end of the day, the decision (and interpretation of the rules) is his to make and we have to accept what the chief eligibility scrutineer will and won't allow.

I think it's great to see so many on here making positive comments and giving ideas on how the proposed rule re-write should be.

I also agree that Firko's suggestion of getting a knowledgeable group of people together to nut out an updated list of follow on models is a good move.
Title: Re: Rule re-write.
Post by: supersenior 50 on February 12, 2014, 01:24:27 pm: As these things always rear up just before a Nats, it appears that's when these issues become important to some.No surprise there.
With that in view it would be interesting to see how many on this thread, or the other 20 pages, actually have ridden, sponsored riders, or in a business affected bythese issues, have in fact been directly involved in say the past three CMX National Championships.
It would also be interesting to see how many had been directly involved in organising or officiating at the last three Nats.
Title: Re: Rule re-write.
Post by: 09.0 on February 12, 2014, 01:54:55 pm: With regards to limiting rear suspension, specifically in relation to twin shock pre75 bikes, the rear should be restricted to 4 inches simply because it's easily done. How many race bikes still run the original shocks? Of the minimal amount that actually do run the originals, how many of them have not been rebuilt? It's easy to buy the correct length shocks or getting the originals modified whilst apart.
Title: Re: Rule re-write.
Post by: firko on February 12, 2014, 04:31:28 pm: Quote
In re dampers with external adjusters, Koni came out with them in steel (model 8211) during the 1960s. The aluminum 8212 was introduced in 1967. Those were for race cars but the technology was there for anyone to buy and copy.
I remember them Michael, not that any of the adjustments made much noticeable difference ;D. I was actually referring to Arnaco shocks which have a modern style stacked shim method of operation, 10 click external dampening adjustment, multi adjustable preload and large dia shafts (I think 15mm). Whenever someone questions the validity of Ohlins, YSS or other modern style shocks with shims and external clicker adjustment for pre '75 I refer them to the Arnacos. I think Curnutts were of similar design but I'm open to greater knowledge on them. I've got a couple of pairs but have never pulled them apart.

Quote
Mark, it looks to me like the problem some people have with "billet" clamps is not that they are machined from solid but rather that some of them look like they are from a much later period than pre-1975. That seems to be a no different problem from running a fat snail expansion chamber exhaust suitable for a 1995 bike on a pre-1975 bike. The problem isn't that a welded steel chamber is out of period, it is that the design is out of period.
That's a part of the problem, some of these aftermarket clamps appear way too modern. The main bone of contention is the fact that triple clamps are considered a 'Major Component' along with the frame, swingarm, forks and engine and our MoMs (Manual of MotorSport) or rule book states ....."All major components must have been manufactured within the period, or be replicas of components manufactured within the period specified for the class in which the machine competes other than those listed in the Components Table" which, to my way of thinking puts anything not replicating something built during the period, in this case, pre '75, as not allowable. The paragraph is included to stop builders using later on non period parts to not only gain performance advantage but to spoil the period appearance of the bike. That's why the addition of alloy swingarms to a bike annoy me so much. I've researched this to the nth degree and can find only Boyd and Stellings*manufacturing aluminium swingarms on a commercial basis prior to 1975 (and OSSA on the first of the Phantoms). Thor, Kosman, DG, FMF, Profab and others didn't produce alloy swingarms for any dirt motorcycle prior to 1975 from what my research can uncover, and in fact there weren't very many producing Chro-Mo swingarms either. It wasn't until the 75-79 period when such stuff became 'must have' fasion items ;).

* There was a company producing solid cast aluminium swingarms prior to 1975 but they're very uncommon and as I write this I can't remember the company's name (A&A perhaps?).
Title: Re: Rule re-write.
Post by: Michael Moore on February 12, 2014, 05:37:13 pm: Yes, Mark, you are thinking of A&A Racing. A friend had one of their cast swing arms on a C15/B25 he ran in AHRMA Premier Lightweight. This looks to be one of them:

http://issuu.com/retromotoonline/docs/bsac15

and also

http://www.b50.org/photos/uploaded/_1e08feae8f0d78c6a9f6bc0995f217be_larryrbswingarm1.jpg

Ernie Earles built an entire chassis (including Earles fork) out of aluminum for a 500cc non-unit BSA twin back in the 50s (featured in the 06/87 Classic Bike and located in the S. Miller museum)

(http://i274.photobucket.com/albums/jj248/guybo27/Miller_Museum_056m.jpg)

Don't forget your Swenco alloy LLF, the OSSA aluminum monocoque RR, the Alta Suzuki aluminum monocoque trials bike with magnesium fork yokes, the CRDC aluminum monocoques used on both RR and MX, Offenstadt RR monocoque, etc. Aluminum is just another metal and different designers used different materials. I suspect that many of the period alloy swing arms are probably less stiff than the steel s/arms. The Ti BSA works bikes were certainly a step in the wrong direction. IIRC the early Suzuki OEM alloy swing arms on the big GS street bikes were heavier than the steel parts they replaced. Some of the modern "replica" alloy s/arms I've seen look pretty dodgy structurally to me. Aluminum may be 1/3 the weight of steel but it is also 1/3 as stiff, so for a given size of tube you'd better have 3X the wall thickness in the aluminum part to have similar stiffness, but once you do that you've got the same weight and much worse fatigue characteristics.

I like steel. :)

FWIW, when he responded to my request for "who knows the earliest instance of machined from solid alloy clamps" Tony Foale told me "I can offer early 1970s but I certainly would not claim to be the first. When I started making frames as a business I then changed to getting basic castings done in magnesium which I machined on a lathe face plate. Prior to that I made a couple sets from the solid."

So we've got at least Tony and the CZ factory making billet clamps in the early 70s.

There are some Curnutt articles here:

http://www.eurospares.com/graphics/suspension/

No shim stacks, they had a floating piston. I've seen mention that Works Perf's Gil V started out by modifying Curnutts, but I don't have anything more than hearsay on that.

I'll admit that I'm biased away from stock motorcycles, having never had a new bike that stayed stock much longer than it took to get it home. Rules that rewrite history by pretending some things didn't happen seem a bad idea. Stock bikes are nice to see now and then and every museum should have some, but our sport is one filled with people like Les Archer racing cammy Nortons on the dirt, or Dennis Jones, Len Harfield and Bob Geeson who built entire race bikes including the engines in their sheds.

If it looks like someone could have built it in the period it is fine by me and I'm happy to see it, because I know there's a good chance that someone probably did build it or something even cooler. But other people have different opinions.

cheers,
Michael
Title: Re: Rule re-write.
Post by: Ted on February 12, 2014, 06:03:35 pm: Quote from: supersenior 50 on February 12, 2014, 01:24:27 pm
As these things always rear up just before a Nats, it appears that's when these issues become important to some.No surprise there.
With that in view it would be interesting to see how many on this thread, or the other 20 pages, actually have ridden, sponsored riders, or in a business affected bythese issues, have in fact been directly involved in say the past three CMX National Championships.
It would also be interesting to see how many had been directly involved in organising or officiating at the last three Nats.

Because I have had a fair bit to say about some mooted changes some want, I will have a say.

A fu..cked wrist prevents me from racing MX. That's why I built a Vinduro bike. Go when you want , stop when you want etc.

However I will be entering two Evo bikes at Toowoomba. They will have two guys from the Heaven club on them.

I have only attended the last CMX in Qld. Am attending this coming PCMX in Qld and will attend the CMX in Port Augusta later in the year.

I sponsored a best effort award at the last CMX and always tip in for any charitable cause that is mentioned, as was the case at the last CMX.

I also helped with scrutineering on the first morning at the last CMX

Just because I can't race anymore does not prevent me from being active in our sport.

Bring in one armed racing Col and I'll be the first entry ;D

Cheers
Title: Re: Rule re-write.
Post by: supersenior 50 on February 12, 2014, 07:20:28 pm: Why defensive Ted ? You sponsored a rider and an award, therefore obviously are directly involved as described in my post.
Title: Re: Rule re-write.
Post by: Ted on February 12, 2014, 07:28:45 pm: Sorry mate, didn't intend it to be ;D

Looking forward to it.
Title: Re: Rule re-write.
Post by: Slakewell on February 12, 2014, 07:54:27 pm: Without starting a thread Hi jack and Im happy to move if you chose to debate this Topic.
Does anyone disagree with the following statements?
Pre78 at the Nats race on mostly smooth terrain and more than 9” travel has no real advantage.
Major travel increases will decrease the bikes turning prowess
Because of counter shaft sprocket location large suspension mods lead to chain problems.
More models don’t fit with in the rules in standard trim than do.
Un engineering or backwards engineering goes against the spirit of our sport.
Most people in 75/77 era were engineering suspension and frame mods.
Title: Re: Rule re-write.
Post by: Ted on February 12, 2014, 08:00:21 pm: Quote from: Slakewell on February 12, 2014, 07:54:27 pm
Without starting a thread Hi jack and Im happy to move if you chose to debate this Topic.
Does anyone disagree with the following statements?
Pre78 at the Nats race on mostly smooth terrain and more than 9” travel has no real advantage.
Major travel increases will decrease the bikes turning prowess
Because of counter shaft sprocket location large suspension mods lead to chain problems.
More models don’t fit with in the rules in standard trim than do.
Un engineering or backwards engineering goes against the spirit of our sport.
Most people in 75/77 era were engineering suspension and frame mods.

True
True
True
False
True
False

My main concern is raising the limit above nine inches will lead to backyarders pushing the limits on what the fork can handle. If they were 43mm forks, I wouldn't care.
Title: Re: Rule re-write.
Post by: FourstrokeForever on February 12, 2014, 08:47:53 pm: Quote from: Ted on February 12, 2014, 08:00:21 pm
Quote from: Slakewell on February 12, 2014, 07:54:27 pm
Without starting a thread Hi jack and Im happy to move if you chose to debate this Topic.
Does anyone disagree with the following statements?
Pre78 at the Nats race on mostly smooth terrain and more than 9” travel has no real advantage.
Major travel increases will decrease the bikes turning prowess
Because of counter shaft sprocket location large suspension mods lead to chain problems.
More models don’t fit with in the rules in standard trim than do.
Un engineering or backwards engineering goes against the spirit of our sport.
Most people in 75/77 era were engineering suspension and frame mods.

True
True
True
False
True
False

My main concern is raising the limit above nine inches will lead to backyarders pushing the limits on what the fork can handle. If they were 43mm forks, I wouldn't care.

Come on Ted, the '75 to '78 era was when most of the frame modifications by the average punter happened. All sorts of shock positions and lengths were tried. Even the minibikes started to get modified "monoshock" frames. Yes Ted, if backyarders start extending more than 9" of wheel travel from a 38mm diameter tube, there will be problems that could result in serious injury from metal fatigue and stresses on the lowers. I would never like to see any diameter fork tube beyond 38mm in Pre78 machines.
Title: Re: Rule re-write.
Post by: Ted on February 12, 2014, 09:03:41 pm: Mick put up " most people in 75/77 era were engineering suspension and frame mods"

That's more than 51%. Not a chance. I agree plenty were, but more than half the grid in every class in every race. Pfffft

You only speak of 38 mm forks. What about all the 35 and 36 mm forks that are also in Pre 78
If you increase Pre 78 travel limits you increase them across the board in all classes

More 125's were sold in this period than all the other classes combined. What do you really think will happen when a bloke tries to get 11 inches out of his 36 mm forks

MA write the rules. MA are also the insurer. Do you honestly believe they would condone these ridiculous travel limits. Negligence in the first degree.
Title: Re: Rule re-write.
Post by: FourstrokeForever on February 12, 2014, 09:26:01 pm: Quote from: Ted on February 12, 2014, 09:03:41 pm
Mick put up " most people in 75/77 era were engineering suspension and frame mods"

That's more than 51%. Not a chance. I agree plenty were, but more than half the grid in every class in every race. Pfffft

You only speak of 38 mm forks. What about all the 35 and 36 mm forks that are also in Pre 78
If you increase Pre 78 travel limits you increase them across the board in all classes

More 125's were sold in this period than all the other classes combined. What do you really think will happen when a bloke tries to get 11 inches out of his 36 mm forks

MA write the rules. MA are also the insurer. Do you honestly believe they would condone these ridiculous travel limits. Negligence in the first degree.

I agree with you on most points and yet you still want to argue. Why? Of course there are smaller diameter fork tubes in pre78. I just used 38mm as an example because 38mm is the maximum diameter of fork tubes allowed in Pre78. Does it make no sense to you that any fork tube under 38mm that is increased in travel limits will be even more dangerous than that of 38mm?

For the record, I wish you would spend more time reading what is written than reacting to what you think is written. I have never once written that I think the pre78 suspension limits should be increased. As a matter of fact, I suggested the travel limit of 9" front and back should remain unchanged.

As for the percentage of racers that modified their suspension during the '75 to '78 period, are you sure there weren't more than not? Can you back your figures up? Do you have proof other than saying you were there? Or are you looking at it from a clubman level where not many could afford to start drastically modifying their bike and were quite happy just to go for a roost with their mates on Sunday?
Title: Re: Rule re-write.
Post by: Davey Crocket on February 12, 2014, 09:48:25 pm: Going by bike sales in the pre78 era, more upgraded to the next years model than tried to modify bikes....next years model was always better unless you rode one of those red things......also, the best bikes in class sold in huge numbers and the others didn't.
Title: Re: Rule re-write.
Post by: firko on February 12, 2014, 10:30:21 pm: Enough of this extended forks bullshit..........Ted you're getting caught up in some vortex where you're stuck on travel increase by modifying stock forks. As someone who's built a lot of specials and know a lot more people who have done the same, not many, if anybody modifies forks for more travel...shit, I never even considered it an option until you started going off. Most builders fit bigger diameter/longer /more efficient forks, forks that come stock with extra travel, not fluck with forks that were inadequate in the first place. Frame changes are about improving geometry and have only a minimal influence on travel. The mods are mostly about getting the bike to turn better, track more efficiently and basically handle better. You and I must have been on different cosmic planes in the late seventies it seems....I recall seeing modified bikes all over the place where I lived in the 75-78 period and it was almost the same here in NSW.
Title: Re: Rule re-write.
Post by: Brian Watson on February 12, 2014, 11:51:42 pm: Well Mark.....I won't go searching for an extra inch of travel in my HVA forks...I lived and raced right thru the middle of the suspension revolution..not many guys had the loot to put different forks in their bikes..but went searching for extra travel by putting kits in the forks.. mostly the Jap guys as I recall... Then there were the guys who bought new bikes each year that didn't need to mod their old bikes.....Leave the suspension limits as they are..it is about re-creating an era...95 % of the guys on the start line raced pretty well stock bikes...
Title: Re: Rule re-write.
Post by: Tossa on February 13, 2014, 12:11:19 am: not only that Watto most of the guys were just damn well enjoying themselves
Title: Re: Rule re-write.
Post by: supersenior 50 on February 13, 2014, 08:21:21 am: Well the "other thread" has gone to the dungeon, this one has gone full circle and done to death, so hopefully time to settle down and get on with enjoying our sport.
Get those kosher bikes entered for the Post Classic Nats, it'll be all good. The Classics have had a run of great events, and it's the Post Classic's turn to shine.
Title: Re: Rule re-write.
Post by: FourstrokeForever on February 13, 2014, 09:24:03 am: Quote from: supersenior 50 on February 13, 2014, 08:21:21 am
Well the "other thread" has gone to the dungeon, this one has gone full circle and done to death, so hopefully time to settle down and get on with enjoying our sport.
Get those kosher bikes entered for the Post Classic Nats, it'll be all good. The Classics have had a run of great events, and it's the Post Classic's turn to shine.

Touche' Col. I hope to be able to make it to the PC's. I'm sure it will be a success. You Queenslanders know a thing or two about promoting and running events.
Title: Re: Rule re-write.
Post by: DJRacing on February 13, 2014, 09:42:35 am: Quote from: Nathan S on February 09, 2014, 04:28:31 pm
Now that lots of people's brains have exploded, here's the same rules with annotations in blue. (The blue bits aren't part of the rules - they help people understand the changes).

16.11 MACHINE ELIGIBILITY
16.11.1 Eligible Machines
16.11.1.1    Only machines conforming to the requirements set out in chapter 16 will be accepted for competition.
16.11.1.2    The onus of proof of eligibility shall rest wholly upon the rider or entrant of the machine. Service and parts manual publication dates are not proof of eligibility.

16.15.7 Acceptable machines and components:
All Eras: (this saves repeating a whole lot of stuff for every category)
a) Major Components are: Frame, swing arm, forks, wheel hubs, triple clamps, engine cases, cylinder(s), and cylinder head(s). A machine's era will be defined by its newest major component. (defining the major components is important - it makes the difference between "do I need to use old tyres?" and "can I fit the forks off my 2005 Honda?")
b) Any major component that is visually similar and operationally indistinguishable from the original will be accepted regardless of the date of manufacture. (I am not happy with "similar" - the word "identical" is too strict for minor differences like casting changes, but "similar" is too vague. Open to input on that one!
This bit also replaces the need to specifically allow identical carry-over models)
ba) Any major component that is visually similar and operationally indistinguishable from aftermarket components available in the era, will be accepted regardless of the date of manufacture. (As above)
c) Any modifications to major components must be using principles and techniques that were available in the era the machine is entered in. (just stops loop-holing tactics)
d) Rear shock absorbers will be in the original position(s), using the original mounting points. (As well as avoiding repeating the same thing over and over again, this kills the "single-shock to twin-shock Evo" bike argument dead)
da) Folding footrests must be fitted.
(I killed "exhaust must follow original lines" because it achieves nothing.
I killed the "must meet the noise test" stuff because its already in 16c)

Pre 60 Solo. This class is intended to represent the formative era of motocross. (Weakly worded - needs input from the old hands).
16.15.7.1    The pre 60 class is for machines that closely represent those built up to (and including) 1959 models.
16.15.7.3    Front wheel travel will not exceed 178mm (7 inches) rear wheel travel will be limited to 102mm (4 inches) measured at the axle.
16.15.7.4    Plastic and fibreglass is not permitted.
16.15.7.6    Period carburettors or Amal Mk1 Concentric.
16.15.7.7 Reed valves are not permitted. (Kind of redundant, but added for clarity)

Pre 65 Solo. This class is intended to represent the first generation of purpose-built motocross bikes. (Again, weakly worded pre-amble - input please)
16.15.8.1    The pre 65 class is for machines that closely represent those that were built up to (and including) 1964 models.
16.15.8.3    Front wheel travel will not exceed 178mm (7 inches) rear wheel travel will be limited to 102mm (4 inches) measured at the axle.
16.15.8.6    Carburettors of any type pre 75 round slide may be used.
16.15.8.7 Reed valves are not permitted. (as for Pre-60)

Pre 70. This class is intended to represent the era where 4-stroke machines lost their dominance and 2-stroke machines became dominant. (Ditto)
16.15.9.1     The pre 70 class is for machines that closely represent those built up to (and including) 1969 models.
16.15.9.2     Front wheel travel will not exceed 178mm (7 inches) rear wheel travel will be limited to 102mm (4 inches) measured at the axle.
16.15.9.4     Carburettors; any type of pre 75 round slide may be used.
16.15.9.5     Reed valves are not permitted.
16.15.9.9    Yamaha XS1 and XS650 engines are eligible.
16.15.9.10    Acceptable follow on models: AJS Stormer 250; Greeves griffon models; Yamaha AT1, DT1, CT1, RT1 without reed valve induction. (tightening up the wording slightly)

Pre 75 Solo. This class is intended to represent the last of the short travel suspension era.
16.15.10.1    The pre 75 class is for machines that closely represent those built up to (and including) 1974 models.
16.15.10.2    Front wheel travel will not exceed 178mm (7 inches) rear wheel travel will be limited to 102mm (4 inches) measured at the axle.
16.15.10.4    Carburettors; any type of pre 75 round slide may be used.
16.15.10.5    XS1 and XS650 engines are eligible.
16.15.10.9    Acceptable follow on models pre 75:
Honda CR125M1, XL250K1, XL350K1, MT250 (all) and MT125 (all)
Yamaha YZ360B, DT250B,
Suzuki TS400 (all).

Pre 78 Solo and Women's Pre-78. This class is intended to represent the transition era between the short travel Pre-75 machines and the long travel Evo machines.
16.15.11.1    The pre 78 class is for machines that closely represent those built up to (and including) 1977 models.
16.15.11.2    Front wheel travel will not exceed 229mm (9 inches) rear wheel travel will be limited to 229mm (9 inches) measured at the axle. (I want to change this to 10", but in the spirit of not changing the regs, I have resisted...)
16.15.11.4    Carburettors; any type of pre 78 round slide may be used.
16.15.11.8    Acceptable follow on models pre 78

CZ 125 1978, CZ400 1978,
Montesa VB, (ditched the "must comply with suspension limits bit" because the bike has to comply with 16.15.11.2 and 16.11.1.1)
Yamaha TT500 1978 (is this correct?)

Evolution. This class is intended to represent the era of long suspension travel, before water-cooling, disc brakes and linkage rear suspension became dominant.
16.15.12.1 The Evo class is for machines that use drum brakes, air-cooling and non-linkage rear suspension, as was commonplace until 1981. It also allows for later machines up to (and including) 1985 models that retained this technology. (yes, 1985. Locking Evo into an era kills off the SexMax and any variation of it, without harming any of the 'real' Evo bikes. It still allows the later Evo Huskies, later CZs, and DT175s(!) )
e) Evolution class bikes must have No linkage suspension, No disk brakes, and Air cooled motors.
16.15.12.4    Carburettors; period flat slide carburettors and any round slide carburettor may be used.
16.15.12.9    The handlebars must be equipped with a protection pad on the cross bar. Handlebars not fitted with a cross bar must be equipped with a protection pad located in the middle of the handlebars covering the handlebar clamps. (not sure if this is supposed to be on the older eras too? Just repeating what's in the current rules).
f) Front forks must be of the non-USD type, where the fork seal(s) move with the front axle. (stops Simmons USDs and 84 KTM USDs).
(I've written this using Dave Tanner's interpretation which was basically 'we don't care if it came from a linkage/water-cooled/disc braked bike, provided the end result has drums, air and no link'. I don't personally agree, but its the closest we've got to an answer to that long running question, so I used it).

Pre 85 Solo This class is intended to represent the era of the first generation of disc front brakes, water cooling, linkage rear suspension and exhaust power valves became commonplace.
16.15.13.1    The pre 85 class is for machines that closely represent those built up to (and including) 1984 models.
16.15.13.2     Carburettors; pre-85 flat slide carburettors and any round slide carburettor may be used.
16.15.13.7    The handlebars must be equipped with a protection pad on the cross bar. Handlebars not fitted with a cross bar must be equipped with a protection pad located in the middle of the handlebars covering the handlebar clamps.

Pre 90 Solo This class is intended to represent the era where rear disc brakes, upside down forks, and the second generation of exhaust power valves became common place. (by second generation PVs, I'm talking about the multi-element ones like KIPS and HPP, rather than YPVS and ATAC).
16.15.14.1    The pre 90 class is for machines that closely represent those built up to (and including) 1989 models.
16.15.14.2    Carburettors; period flat slide carburettors and any round slide carburettor may be used.
16.15.14.7    The handlebars must be equipped with a protection pad on the cross bar. Handlebars not fitted with a cross bar must be equipped with a protection pad located in the middle of the handlebars covering the handlebar clamps.

(I know sod-all about sliders and sidecars, and there doesn't seem to be much stress around them, so I assume the rules for those are pretty well right?)
16.16 SLIDERS
16.16.1 Slider Frames
16.16.1.1    The frame must:

Have a conventional swing arm rear suspension with twin shock absorbers,
Have a front wheel diameter of 23”,
Have a rear wheel diameter of 19”,
Have rear tyres with a maximum tread pattern depth of 8mm,
Not be fitted with leading-link front forks.

16.16.2 Slider Solo Engines
16.16.2.1    The slider engine must:

Be a single cylinder,
When four stroke be 2- valve push rod operation,
Have a single spark plug,
Be vertical in the chassis,
Be fitted with a round slide carburettor, or
Be a period two stroke compatible with class entered.

16.16.3 Slider Gearbox: Classic Long Track
16.16.3.1    The gearbox must have at least two gears.
16.16.4 Slider Sidecar Frames
16.16.4.1    Conventional type frames as used prior to 31st December 1976 must be used.
16.16.5 Slider Sidecar Engines
16.16.5.1    Engines must have been manufactured before 31st December 1976.
16.17 SIDECARS
16.17.1 All Classes
16.17.1.1    Left -hand and right -hand sidecars may compete against each other in Classic Motocross.
16.17.2 Frames and Parts
16.17.2.1    For the Pre-1975 classes, all performance parts except frames must be manufactured before 31st December 1974 and must comply with the following:

Wheel track measurement, taken between the longitudinal centres of the rear and sidecar wheels must be between 810mm and 1100mm,
The minimum ground clearance must be 175mm unladen,
The maximum lean of the motorcycle at saddle height mustbe 50mm,
The dimensions of the sidecar baseboard in plain view, taken from a line drawn no further rearwards than the lowest point of the front down-tube to the forward most point of the sidecar wheel tyre and terminating no further rearwards than a line drawn at right angles to the machine from the rearmost point of the rear tyre, must be:
At least 760mm long adjacent to the sidecar wheel,
At least 300mm wide with at least 25mm radius to all corners.
There must be no more than 50mm between baseboard and motorcycle and between baseboard and sidecar wheel. The baseboard must be arranged so as not to allow the passenger’s feet to be trapped,
There must be no less than 4 sidecar attachment points,
Stirrup fitting for the passenger’s feet are not permitted,
Handholds:
Must be finished with a loop of at least 100mm,
Must not project beyond a line taken with the outer edge of the sidecar mudguard or bodywork,
Adjacent to the nose section of the sidecar and less than 200mm from the track surface must be at an angle of at least 45° from the horizontal.
The rear end of the rear wheel mudguard must terminate not more than 65° above a horizontal line drawn through the rear wheel axle and be valanced to baseboard level on the inside,
The sidecar mudguard must cover at least 135° of the periphery of the wheel and be valanced to baseboard level on the inside,
No machine may be fitted with scoop or paddle tyres,
Suspension travel must not exceed:
152mm (6”) 178mm (7”) measured at the front axle,
102mm (4”) at the rear axle.
Rear tyre width must not exceed 135mm (5.3”),
Brakes:
Front – single caliper, single disc may be fitted provided they were manufactured before 31st December 1974,
Rear – rear disc brakes may be used provided they were fitted as standard equipment for that particular combination.

Only round-slide carburettors manufactured within the relevant period may be used,
Engine capacity must be up to 1300cc.

16.17.2.2    Pre-1985 is for sidecars constructed with motors manufactured before 31st December 1984.
16.17.2.3    A lanyard operated ignition cut-out switch, operating on the primary circuit, must be fitted to the following with a maximum length of one metre:
DISCIPLINE

MACHINE
Motocross    Sidecars
Dirt track    Sidecars
16.17.2.4    Pre-1968 will be for sidecars constructed from road going frames and all major components are those commercially available within the period.
16.17.2.5    The following table sets out the machines and components which eligibility scrutineers may use as a guide in determining eligibility. Entrants must prove eligibility of machines not listed below.
MAKE

MODEL(S)
Wasp    All up to and including RT2, RT8 and RT14
Hagon    All up to 31st December 1974
Yamaha    XS 650 all models
Honda    Any K series
Norton    All 750, 850 to Mk2 only
Westlake    All up to 850cc and 31st December 1974
Triumph    All up to T150
CCM    All BSA B50 based models
Title: Re: Rule re-write.
Post by: supersenior 50 on February 13, 2014, 10:02:53 am: Just to clarify, Womens Pre78 means any machine up to Pre78, not just 75, 76, 77 models.
Title: Re: Rule re-write.
Post by: FourstrokeForever on February 13, 2014, 10:18:04 am: CZ 125 1978, CZ400 1978,
Montesa VB, (ditched the "must comply with suspension limits bit" because the bike has to comply with 16.15.11.2 and 16.11.1.1)
Yamaha TT500 1978 (is this correct?)

I don't see any reason why the 1978 can't be listed as a follow on model. It is basically the same machine as was produced in 1977.

Pre 75 Solo. This class is intended to represent the last of the short travel suspension era.
16.15.10.1 The pre 75 class is for machines that closely represent those built up to (and including) 1974 models.
16.15.10.2 Front wheel travel will not exceed 178mm (7 inches) rear wheel travel will be limited to 102mm (4 inches) measured at the axle.
16.15.10.4 Carburettors; any type of pre 75 round slide may be used.
16.15.10.5 XS1 and XS650 engines are eligible.
16.15.10.9 Acceptable follow on models pre 75:
Honda CR125M1, XL250K1, XL350K1, MT250 (all) and MT125 (all)
Yamaha YZ360B, DT250B,
Suzuki TS400 (all)

Just to clarify on the acceptable follow on models.....

When you state the CR250M1, are you referring to the 1975 Model? And with the XL250K1 and XL350K1, are you referring to the centre port engined XL's?

Sorry to be a pain in the rectal area, but do the bikes that were manufactured with slightly more than 4" rear suspension have to comply with rule 16.15.10.2?

Great job everybody.
Title: Re: Rule re-write.
Post by: FourstrokeForever on February 13, 2014, 10:25:20 am: Quote from: firko on February 13, 2014, 10:09:26 am
It's a pity that the focus of the thread turned to personal agenda and the original intent seemed to go out the window. I'm pissed with myself for allowing myself to get involved in the pre 78 suspension bullshit which helped the thread come to a premature siezeure. For that I apologise. When Nathan first posted what must have taken him ages to collate, I was excited and thought that this could finally be the thread where everyone could contribute for the betterment of the rulebook and the overall sport. I genuinely thought that the last five years of folks whingeing on here about the inadequacies in MoMs (often with good reason) would inspire a rush of contributions full of positive ideas to help make the rulebook more user friendly. It started off well but as happen to most serious threads, it turned into yet another soap box for personal agenda. Once again I probably contributed to that by adding opinion to my ideas which in retrospect was a stupid rookie mistake. I hope Nathan can get enough out of what's on here to do a rewrite on the rules. He and I rarely see eye to eye on anything but in this case I admire his having a go and hope that the thread can still contribute something positive to his project.

In the greater scheme of things Firko, there was no mud slinging or personal attacks, well at least in this thread. And I think on the whole, there has mostly been food for thought brandied about rather than excess argument about a certain era.
Nathan has done a great job and should be commended for his efforts by all and sundry. He has obviously taken "Nathan" out of the equation and given thought to what the majority of feedback received wanted and hoped for.
Title: Re: Rule re-write.
Post by: Big Bird on February 13, 2014, 11:53:15 am: I have just stumbled across this thread after a period of a few weeks where I've spent little time here. My fullest congratulations to Nathan for biting the bullet and giving the rules re-write a red hot go. And more so for taking the time to annotate it and explain the intent. I'll be sure to work through it all before I make any detail comment, but Nathan you have my full respect for having such vision, and acting on it to deliver such a comprehensive review.

Cheers,

Geoff
Title: Re: Rule re-write.
Post by: KTM47 on February 13, 2014, 12:25:31 pm: Quote from: supersenior 50 on February 13, 2014, 10:02:53 am
Just to clarify, Womens Pre78 means any machine up to Pre78, not just 75, 76, 77 models.

Col for the PCMXC supp-regs we wrote the Women's class as (up to Pre 90) The same could be done for the Classic Champs. Up to means it includes everything under Pre 90 etc. It needs to be written as "up to" because if you use the correct wording for Pre 78 it is only open to 75, 76 and 77 model bikes.

My view is the wording for all classes should be similar to Pre 78 so the class/es are only open to the bikes from that era eg Pre 90 85 to 89 models, plus carry over models.

Kevin
Title: Re: Rule re-write.
Post by: supersenior 50 on February 13, 2014, 02:20:15 pm: Way ahead of you Kev. Both 2012 and 2013 Womens Class was "up to and including Pre78 machines"
I only posted the clarification to add to Nathan's contribuition
Title: Re: Rule re-write.
Post by: Rossvickicampbell on February 13, 2014, 04:54:51 pm: quick one - when the YZ360B is classed as a follow on - that also applies to the 250B?
Title: Re: Rule re-write.
Post by: KTM47 on February 14, 2014, 09:58:26 am: This is one of the rules that needs updating in the MOMS. The facts are if an official read the rules as written there are a lot of things that are generally accepted that could be knocked back.

But there is the section in the front that says .

THE PHILOSOPHY AND STRUCTURE OF THE GENERAL COMPETITION RULES

No set of Rules can anticipate every issue which may arise in the conduct of a sport, especially one with as wide a variety of disciplines and competing interests as exist in motorcycling. The philosophy of these Rules is that good sense, cooperation and a fair and reasonable interpretation of reasonable Rules should be more important than “Rule Book Racing”.

So using the above if the YZ360B is legal then the YZ250B probably should be also.
Title: Re: Rule re-write.
Post by: firko on February 14, 2014, 11:12:33 am: Quote
quick one - when the YZ360B is classed as a follow on - that also applies to the 250B
Ross, the YZ250/360B isn't regarded as a flow on, being a designated '74 model it's considered a legitimate, legal pre 75 bike. To answer your question as a hypothetical though, whatever goes for the 250 goes for the 360.
Title: Re: Rule re-write.
Post by: JohnnyO on February 14, 2014, 12:32:04 pm: The YZ360b and 250b are 74 models and have been legal for pre 75 for years.. Why are we going down this road again??
Title: Re: Rule re-write.
Post by: firko on February 14, 2014, 01:28:22 pm: Quote
Why are we going down this road again??
I was wondering the same thing.
Title: Re: Rule re-write.
Post by: supersenior 50 on February 14, 2014, 05:37:45 pm: I suggest everyone should read "The philosophy and structure of the GCRs" at the beginning of the on line MoMs, take a deep breath and a cold shower and settle down.
We are all hoping for a trouble free and enjoyable event ( following two failed attempts), and speaking as one who knows, it is a big task for volunteers to take on running such an event. Not to mention a big financial risk for the host club.
Those not directly involved should take a back seat and leave their thoughts until after the Nats, then go through the proper channels. I have proved it works.
Those owners/riders who are DIRECTLY involved, if wanting to do their part in assisting the volunteers to run a harmonious event, can fit Evo sourced components, enter Pre85, or take the third choice. There is obviously split opinion on the OEM meaning, so going back to "The philosophy..." and the spirit of what we are about, take the heat off the volunteer officials and do our bit to avoid agro at these titles.
Title: Re: Rule re-write.
Post by: Rossvickicampbell on February 14, 2014, 06:52:40 pm: sorry Firko/JO - just read it as was written previously - yes the Bs were a legitimate model - not a flow on - but was wondering why the 360 was listed and not the 250 - my bad - not opening that bag again ;D
Title: Re: Rule re-write.
Post by: DJRacing on February 15, 2014, 04:49:30 pm: Nathan I hope you don't mind but I have listed a few thoughts in Red next to yours and maybe some discussion (not arguments) might take place by the mature and informative people of this forum.

Quote from: Nathan S on February 09, 2014, 04:28:31 pm
Now that lots of people's brains have exploded, here's the same rules with annotations in blue. (The blue bits aren't part of the rules - they help people understand the wording.

Pre 78 Solo and Women's Pre-78. This class is intended to represent the transition era between the short travel Pre-75 machines and the long travel Evo machines.
16.15.11.1    The pre 78 class is for machines that closely represent those built up to (and including) 1977 models.
16.15.11.2    Front wheel travel will not exceed 229mm (9 inches) rear wheel travel will be limited to 229mm (9 inches) measured at the axle. (I want to change this to 10", but in the spirit of not changing the regs, I have resisted...). No more than 9" front and rear travel with a 10% greater allowance for bikes still fitted with the manufacturers original shocks and forks (9.9" or 251.4mm).
16.15.11.4    Carburettors; any type of pre 78 round slide may be used.
16.15.11.8    Acceptable follow on models pre 78

CZ 125 1978, CZ400 1978,
Montesa VB, (ditched the "must comply with suspension limits bit" because the bike has to comply with 16.15.11.2 and 16.11.1.1)
Yamaha TT500 1978 (is this correct?)

Evolution. This class is intended to represent the era of long suspension travel, before water-cooling, disc brakes and linkage rear suspension became dominant.
16.15.12.1 The Evo class is for machines that use drum brakes, air-cooling and non-linkage rear suspension, as was commonplace until 1981. It also allows for later machines up to (and including) 1985 models that retained this technology. (yes, 1985. Locking Evo into an era kills off the SexMax and any variation of it, without harming any of the 'real' Evo bikes. It still allows the later Evo Huskies, later CZs, and DT175s(!) )
e) Evolution class bikes must have No linkage suspension, No disk brakes, and Air cooled motors.
16.15.12.4    Carburettors; period flat slide carburettors and any round slide carburettor may be used.
16.15.12.9    The handlebars must be equipped with a protection pad on the cross bar. Handlebars not fitted with a cross bar must be equipped with a protection pad located in the middle of the handlebars covering the handlebar clamps. (not sure if this is supposed to be on the older eras too? Just repeating what's in the current rules).
f) Front forks must be of the non-USD type, where the fork seal(s) move with the front axle. (stops Simmons USDs and 84 KTM USDs).
(I've written this using Dave Tanner's interpretation which was basically 'we don't care if it came from a linkage/water-cooled/disc braked bike, provided the end result has drums, air and no link'. I don't personally agree, but its the closest we've got to an answer to that long running question, so I used it).

16.15.12 Evo class.
This class is intended to represent the era of long travel suspension (LTS) before linkage rear suspension and/or water cooled motors and/or disc brakes.
16.15.12.1 The period or era for Evo is generally up to and including 1981 but no more than 1985. 16.15.12.2 Evolution bikes have to have been manufactured with, Non Linkage suspension, Drum Brakes and Aircooled Motors.
a) All parts from those bikes are permissible as are all after-market parts of this era.
b) Modifying your bike with other major parts(other than after-market parts) from a newer era or technology is not allowed (no USD forks).

By the way, YES, I am an outsider so I have no personal agenda other than if you guys (in Oz) get it right then other places may adopt your rules.
All I have done is read what people seem to want from their rules and put pen to paper.
As most in here and the "other thread" have said some rules need tweaking/ clarifying so it is fair, simple and easy.
Sometimes looking from the outside in can be more clear and less bais.
Anyway gentlemen, some times a simple Yes or No answer can be a lot more effective than a long drawn out opinion, so with that I will let the games begin.
Title: Re: Rule re-write.
Post by: VMX247 on February 17, 2014, 07:54:45 pm: Is anyone submitting one or two rule changes for next years GCR's ? or we going to keep going around in a circle. :P
Title: Re: Rule re-write.
Post by: KTM47 on February 18, 2014, 12:37:37 pm: Quote from: KTM47 on February 14, 2014, 09:58:26 am
This is one of the rules that needs updating in the MOMS. The facts are if an official read the rules as written there are a lot of things that are generally accepted that could be knocked back.

But there is the section in the front that says .

THE PHILOSOPHY AND STRUCTURE OF THE GENERAL COMPETITION RULES

No set of Rules can anticipate every issue which may arise in the conduct of a sport, especially one with as wide a variety of disciplines and competing interests as exist in motorcycling. The philosophy of these Rules is that good sense, cooperation and a fair and reasonable interpretation of reasonable Rules should be more important than “Rule Book Racing”.

So using the above if the YZ360B is legal then the YZ250B probably should be also.

So as I see it the YZ360B and YZ250B are not carry over models they are recognised as 1974 models. So the reference to the 360B in the carry over models is wrong.

Kevin
Title: Re: Rule re-write.
Post by: Rossvickicampbell on February 18, 2014, 02:38:48 pm: correct.
Title: Re: Rule re-write.
Post by: supersenior 50 on February 18, 2014, 11:25:00 pm: Please see my reply 17 on the Maico/Evo rules thread
Title: Re: Rule re-write.
Post by: FourstrokeForever on February 19, 2014, 12:37:15 am: Fark my old boots....does the sport really need to keep on going over the same old ground?
Title: Re: Rule re-write.
Post by: supersenior 50 on February 19, 2014, 11:08:18 am: Exactly
Title: Re: Rule re-write.
Post by: Rossvickicampbell on February 19, 2014, 12:02:31 pm: TBM - which bit are you talking about - if it is in reference to the YZBs - my mistake in what I was looking at - not going over old ground.

cheers
Title: Re: Rule re-write.
Post by: matcho mick on February 19, 2014, 12:05:30 pm: the part that i find sad (& telling) is the post "who's going to the nats" gets 14 replies,this shit,(literally) gets 11 forking pages :o, :P
Title: Re: Rule re-write.
Post by: supersenior 50 on February 19, 2014, 12:24:41 pm: Right on Mick. However if you take the "Scutineering...." thread, Ebay Montessa thread and Maico Evo rules thread,plus this one, there are 40 pages.
Title: Re: Rule re-write.
Post by: JohnnyO on February 19, 2014, 12:31:09 pm: Quote from: matcho mick on February 19, 2014, 12:05:30 pm
the part that i find sad (& telling) is the post "who's going to the nats" gets 14 replies,this shit,(literally) gets 11 forking pages :o, :P
That just shows that hardly any of the jibberers posting all the crap on here are going to the Nats..
Title: Re: Rule re-write.
Post by: micks on February 19, 2014, 01:38:35 pm: along the same lines as matcho mick. we done 20 pages on "do you moto 100" (how`s that class going?) in june 2008 but when ask by magoo (rip) about "rule book adjustments" in june 2008 it got 7 pages and here we are today.
Title: Re: Rule re-write.
Post by: evo550 on February 19, 2014, 02:05:30 pm: Quote from: JohnnyO on February 19, 2014, 12:31:09 pm
Quote from: matcho mick on February 19, 2014, 12:05:30 pm
the part that i find sad (& telling) is the post "who's going to the nats" gets 14 replies,this shit,(literally) gets 11 forking pages :o, :P
That just shows that hardly any of the jibberers posting all the crap on here are going to the Nats..
Why does it effect only Nats riders? Don't the rules apply across all levels of racing, Club, State and National.
Bet if I turned up to a race day with a '84 KTM USD forks/drum brake set up in the EVO class a $hit fight would erupt.
Not trying to start a slinging match, just applying the new rule interpretation.
Title: Re: Rule re-write.
Post by: firko on February 19, 2014, 02:52:09 pm: I know I vowed to stay away from these posts once they start turning into slagging matches but I think the below can contribute something positive to the subject. If you disagree with my take on it feel free to offer up intelligent debate and reasons for your objection but if it starts to turn into a slag match I'm out of here along with the thread. ;)

The AHRMA is currently debating to include a new class to be called EARLY SPORTSMAN STOCK. Tahitian Red has previously discussed it on here in posts to do with his RT1 Early Stock project. Without going into unnecessary detail on rules that won't effect us here, the eligibility criteria is very similar to our pre '70 but is more performance and technology based. Following is the machine eligibility list with bikes that don't fit into our pre 70 eligibility but possibly deserve to be included as flow ons.
11.1.8 EARLY SPORTSMAN STOCK 250: Certain 250 class machines introduced after the Classic era. some of the bikes in red are obvious inclusions despite their post 1970 release date (Kawasaki Bison 250, Bighorn 350, Yamaha AT-1 and CT-1, OSSA Stilleto 5 sp, Honda SL/CL 350 and Suzuli TS185) while others such as the QUB Greeves, BSA B50, Triumph TR-5, Maico 501, and Cooper 250 are at least worth debating their inclusion. My personal take is to disallow the Cooper 250, B50, TR5 and Maico 501 but allow the rest into pre 70 on the grounds that they're not competitive in pre 75 and that their technology base leans more towards pre 70 in concept.
Eligible machines are:
Bultaco Pursang Model 42-48-68
CZ 250 Sidepipe
Cooper MX 250
Montesa 5 speed Cappra
Husqvarna 250 Round Case 4-speed
SB Maico Square Barrel
OSSA 5 speed Stilleto
Yamaha DT-1
Suzuki 250 Savage
Suzuki 185
Kawasaki 175 F7
Kawasaki 250 Bison F8, F81
Yamaha AT-1, CT-1

11.1.9 EARLY SPORTSMAN STOCK 500: Certain Open class machines after the Classic era.
Yamaha RT-1
American Eagle 360/405
SB Maico Square barrel
Husqvarna Round Case 4-Speed
CZ 360 Sidepipe
501 Maico
Greeves QUB 380
BSA B50
Kawasaki 350 Bighorn
Honda SL &CL-350
Triumph TR5 MX
Title: Re: Rule re-write.
Post by: matcho mick on February 19, 2014, 03:26:46 pm: aarrrggghhh delete it quick,before too many see it firko,my whole point is ,it doesnt have to be positive/negative,people just want to argue the point,you've just added more petrol to the fire :o
look at evo's post,i know he's not going to do that,(just coz he can ::)),he's not stupid,just saying,& again thats my point, go race,it's not rocket science!!, :P
Title: Re: Rule re-write.
Post by: KTM47 on February 19, 2014, 03:36:14 pm: Quote from: evo550 on February 19, 2014, 02:05:30 pm
Quote from: JohnnyO on February 19, 2014, 12:31:09 pm
Quote from: matcho mick on February 19, 2014, 12:05:30 pm
the part that i find sad (& telling) is the post "who's going to the nats" gets 14 replies,this shit,(literally) gets 11 forking pages :o, :P
That just shows that hardly any of the jibberers posting all the crap on here are going to the Nats..
Why does it effect only Nats riders? Don't the rules apply across all levels of racing, Club, State and National.
Bet if I turned up to a race day with a '84 KTM USD forks/drum brake set up in the EVO class a $hit fight would erupt.
Not trying to start a slinging match, just applying the new rule interpretation.

Yes that is correct there is only one rule book but a thousand intrepidations. That is the major problem riders are let get away with things at club level because no one wants to be the bad guy.
Title: Re: Rule re-write.
Post by: supersenior 50 on February 19, 2014, 04:08:44 pm: Time to go
Title: Re: Rule re-write.
Post by: firko on February 19, 2014, 06:49:47 pm: Well that went well.....I spend an hour compiling a positive post with what I thought would be good ideas but all I get is "delete it before the idiots see it" message both on here and by PM. What the fluck has happened to our ability to debate important and interesting points without it turning to shit? Have the lunatics indeed taken over the asylum? I'll leave it up because the flow on criteria for pre 70 and pre 75 could do with a tune up but I suspect that I'm the only one who gives a rats
Title: Re: Rule re-write.
Post by: matcho mick on February 19, 2014, 08:47:43 pm: ;D ;D ;D ;D ;D ;D :o lol mate, :P
Title: Re: Rule re-write.
Post by: KTM47 on February 19, 2014, 10:34:43 pm: Quote from: firko on February 19, 2014, 06:49:47 pm
Well that went well.....I spend an hour compiling a positive post with what I thought would be good ideas but all I get is "delete it before the idiots see it" message both on here and by PM. What the fluck has happened to our ability to debate important and interesting points without it turning to shit? Have the lunatics indeed taken over the asylum? I'll leave it up because the flow on criteria for pre 70 and pre 75 could do with a tune up but I suspect that I'm the only one who gives a rats

Mark I agree the Classic and Post Classic rules need adjusting, but I don't think here is the right place to discuss it. To much crap.
Title: Re: Rule re-write.
Post by: firko on February 19, 2014, 10:59:15 pm: I agree......sadly Kevin whenever something important starts up here it turns to shit. I appreciate Nathans intent and hope something comes out of it. I'll work quietly off here and compile a list of possible flow ons for pre 60 right through to pre 78 (my knowledge taps out at around 1980ish) and post a thread when it's not so volatile on here.
Title: Re: Rule re-write.
Post by: FourstrokeForever on February 20, 2014, 09:41:41 am: Quote from: firko on February 19, 2014, 06:49:47 pm
Well that went well.....I spend an hour compiling a positive post with what I thought would be good ideas but all I get is "delete it before the idiots see it" message both on here and by PM. What the fluck has happened to our ability to debate important and interesting points without it turning to shit? Have the lunatics indeed taken over the asylum? I'll leave it up because the flow on criteria for pre 70 and pre 75 could do with a tune up but I suspect that I'm the only one who gives a rats

No, you're not the only one who gives a rats Mark. My knowledge of the era is not any where near as comprehensive as yours is. I do know a bit about the BSA's so I can say that I agree that the B50 and TR5 should remain in Pre75. They are competitive in the Pre75 era with the right rider on board. Besides, if the BSA and Trumpy B50 were to get bumped back to Pre70, then you'd also have to reconsider where the B44 sits and then the B40....
Title: Re: Rule re-write.
Post by: DJRacing on February 21, 2014, 07:44:48 pm: Pre 78.
I have thought long and hard on this class because it is one of my personal favourites and a very exciting time in motocross history. Without trying to change to much (rules) but still allowing people to modify and experiment with suspension as what was happening in the day. I'm not sure what the longest travel was for a stock bike at the time(1977) and (including flow-ons) but that's what the 10% greater than 9" is for so that stock suspension doesnt have to be restricted. Although Pre78 has suspension restictions and obviously back in the day there were none but they couldnt see into the future as we can see back in the past, so hence the 9" rule or the 10% greater for the last of the bikes of that era(pre78). The rule allowing up to 9" of travel for after-market or new suspension is so older bikes or people trying to ridiculously suspend there bikes don't lose there identity of Pre78 and start looking more like an Evo bike, but can still be competitive against the latest in the class in a racing situation. I agree with what has been said about altering suspension mounts for the purpose of re-creating the era. I hope everyone can understand what I have just written above because Pre78 is truly a piece of MX history and its identity should never be lost.

Pre 78 Solo and Pre 78 Woman's.
This class is for showcasing the era when the revolution suspension travel wars began. Lots of ideas and innovations were tried and tested. This class is here for that reason.

16.15.11.1 The pre 78 class is for machines that were (or could have been) built, up to and including 1977.

16.15.11.2 No more than 9" front and rear travel with a 10% greater allowance for bikes still fitted with the manufacturers original shocks and forks (9.9" or 251.4mm).
*note (these measurements can be altered to be more correct with the bikes of the era

16.15.11.3 Suspension mounts maybe altered/moved but must remain within the parameters of the Era. The same number of shocks must still be used unless altering to a mono shock cantilevered type suspension.

16.15.11.4. Any type of round slide carburettor of the Era can be used.

16.15.11.5. All After-market, special and/or optional production parts of the Era are allowed, including major components. New parts must be compliant with what was available in the Era.

16.15.11.6 Acceptable follow on models for Pre78,
CZ 125 1978, CZ400 1978, Montesa VB, Yamaha TT500 1978

I think/hope the above rules are what most people have asked for and that they are open enough to encourage more stock and modified bikes with limitations a more equal competitiveness (not that it wasnt already) on race day, and allowing the older bikes the ability to be modified as was in the day.
Title: Re: Rule re-write.
Post by: Ted on February 21, 2014, 08:14:16 pm: What's your opinion on this one DJ

The eligibility scrutineer has stated that Evo is not limited to Pre 85, Pre 90 ,and is not an era or period.

The MoMS state " period flat slide and any round slide carburettors can be used "

Seeing as there is no period limit I will be entering a bike with a 2014 Mikuni TM 38 flat slide carby bolted to a 465 H.
Title: Re: Rule re-write.
Post by: DJRacing on February 21, 2014, 09:18:49 pm: Quote from: Ted on February 21, 2014, 08:14:16 pm
What's your opinion on this one DJ

The eligibility scrutineer has stated that Evo is not limited to Pre 85, Pre 90 ,and is not an era or period.

The MoMS state " period flat slide and any round slide carburettors can be used "

Seeing as there is no period limit I will be entering a bike with a 2014 Mikuni TM 38 flat slide carby bolted to a 465 H.

Ted that's a funny one because on one hand the rules state ;
16.15.12.3 All components will be of the period the machine was manufactured:
But as there is no defining time period for Evo (stated by an offical from MA) then does that mean the year the bike was made? Or does it mean any carb off any Aircooled motor can be used or does it mean any carb fitted to a reed block or 'V' block power reed could be used??
Although looking at rule;
16.15.12.4 Carburettors; period flat slide carburettors and any round slide carburettor may be used.
Once again I'm unsure of the period they mean here because the period is on-going because Aircooled motors are still being made. Is the 'Period' went the bike was made, or when the last bike made with an Aircooled motor??

Common sense (which can't be counted on because rules have been put in place of) would suggest that rules,
16.15.12
16.15.12.1
16.15.12.2
16.15.12.3
would all be combined with the notion that all bikes were manufactured with
No linkage suspension,
No disk brakes,
Air cooled motors.
so then the PEROID that they talk about would be when a bike is/was manufactured with all the above three governing factors.
But as has been stated, this isn't the case and components from other periods can be used if it is bolted to other parts that are the same e.g. Forks and drum-brakes, so if a carb is bolted to a reed or an air filter does it mean it can be used because the period is the same. Modern 2014 air filter - carb - reed or Evo air filter - carb - reed ??
To answer your question Ted, I'm sorry I can't, I am at a loss to understand the meanings of the rules of Evo that have been presented to us now.
Title: Re: Rule re-write.
Post by: Ted on February 21, 2014, 09:24:43 pm: It would have to be deemed legal . As you said any OEM drum brakes can be used. They still make drum brakes today. The carby fits into that period.
Title: Re: Rule re-write.
Post by: DJRacing on February 21, 2014, 09:39:39 pm: Quote from: Ted on February 21, 2014, 09:24:43 pm
It would have to be deemed legal . As you said any OEM drum brakes can be used. They still make drum brakes today. The carby fits into that period.

That's exactly what I'm saying Ted, with no defining period I struggle to see how it wouldn't be legal.