Author Topic: 1973 shock position  (Read 4825 times)

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oldfart

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1973 shock position
« on: February 07, 2010, 08:04:11 pm »
If this was legal back in 1973. it should be ok today  Yes or No
http://www.mxworksbike.com/Namur%201973%20005_W.htm

« Last Edit: February 07, 2010, 08:07:43 pm by oldfart »

oldfart

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Offline brent j

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Re: 1973 shock position
« Reply #2 on: February 07, 2010, 09:04:18 pm »
For pre 75?

As long as it has less than 4" travel maybe but then that bike's not a production model so I don't know that the fact that it was run at that time would count.

Brent
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oldfart

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Re: 1973 shock position
« Reply #3 on: February 07, 2010, 09:23:08 pm »
Yes it is a hard call, just making mention that suzuki raced in 1973 with forward mounted shocks on swing arm - top mount remained in same position with a bit of after hours handy work to  frame rail .

Offline Davey Crocket

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Re: 1973 shock position
« Reply #4 on: February 07, 2010, 09:48:28 pm »
Your not allowed to move the shock mounting positions Stu - top or bottom but you can use a different lenght shock to suit your needs but wheel travel must not be more than 4" or 105mm.
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DR

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Re: 1973 shock position
« Reply #5 on: February 08, 2010, 07:23:45 am »
so you can run a bling aftermarket swingarm or another swingarm from another make from that era with different mount positions but you can't move the stock mounts on a stock '73 arm when building a project ??? hmmmm..if the travel remains status quo then where lies the problem? ;) if you want to get real picky the rules state,

'The machine 'must' look like the original' 

Rules out all aftermarket swingarms, forks and triples period! ;) just build it and ride it and worry later..sheep stations are a dime a dozen  :D
« Last Edit: February 08, 2010, 07:33:36 am by Doc »

TM BILL

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Re: 1973 shock position
« Reply #6 on: February 08, 2010, 08:02:27 am »
So say mr Good lent Stu the 73 RN as pictured , could Stu run it in pre 75 open at the nats  ???
if not why not  ;)

Offline Davey Crocket

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Re: 1973 shock position
« Reply #7 on: February 08, 2010, 08:13:45 am »
As long as the suspension travel stays within the boundry's no problemo ;), the 72 was probably nicer - weighed a lot less and probably was within the suspension limit. I dont think we've seen Stu on a bone shaker yet?, he's usually wobbling around on a 4 stroke lounge chair!!! ;D
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oldfart

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Re: 1973 shock position
« Reply #8 on: February 08, 2010, 08:16:58 am »
Bill , you stole my punch line.

TM BILL

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Re: 1973 shock position
« Reply #9 on: February 08, 2010, 09:07:56 am »
 :-[ :-[ :-[

And the fact remains that that bike is a 73 model and the class is pre 75  ??? however it has more than 4 inches rear travel .

Is the bike wrong or the rule  ??? or was there a 4" rule in 1973  :D

Last time we saw stu on a bone shaker it was Docs TSM 400 at Coffs  ;)
« Last Edit: February 08, 2010, 09:12:47 am by TM BILL »

Offline GMC

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Re: 1973 shock position
« Reply #10 on: February 08, 2010, 10:29:10 am »
Just what we need, another debate about rules ::)

Finding a model or aftermarket part that had more than 4” travel before 75 isn’t that hard. Maybe you Suzuki guys should step out of your sheds and look around.
Maico & YZ’s both had more than 4” before 75.
CMS aftermarket frames for CZ’s and Bultaco’s did too.
And probably most works bikes if you study them a bit closer.

There is no argument about longer travel existing before 75.
The Pre 75 class is more about the Era of 4” travel than preserving the year 74.
If you want to run an RN then it would be in the same boat as common as mud LTR Maico’s

Pre 75 is probably the wrong name for the class as it seems many want to be anal about what was around at the time.
The restrictions are about classifying bikes that are similar.
We are all happy to group bikes together by engine capacity 125cc, 250cc etc.
Suspension would be the next thing after engine capacity to make a difference to a bikes performance so bikes are categorized by travel limits.
Makes sense to me.
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firko

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Re: 1973 shock position
« Reply #11 on: February 08, 2010, 12:14:39 pm »
Quote
so you can run a bling aftermarket swingarm or another swingarm from another make from that era with different mount positions

In a word, no you can't Chris. Sure you can run the bling swingarm but it must conform to two criteria: 1 It must be manufactured or be an exact replica of an item made prior to 1975 and 2: The suspension pick up points must be in the same position as the standard swingarm. Simple.

The 7"-4" suspension travel rule has been in use in Australia since 1988, the UK since 1980 and the USA since 1982 and it's served us well. Why do people, after all this time, still try to find loopholes and/or conspiracy theories in a rule that's the very essesence of simplicity?

TM BILL

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Re: 1973 shock position
« Reply #12 on: February 08, 2010, 12:15:29 pm »
[quote

Finding a model or aftermarket part that had more than 4” travel before 75 isn’t that hard. Maybe you Suzuki guys should step out of your sheds and look around.
Maico & YZ’s both had more than 4” before 75.
[/quote]

Then why oh why is the class restricted to 4"  ??? wouldn't it be equally as simple to have 5 or 6 inches  ???

I dont believe its looking for loopholes or conspirices , personally you could give me Joels RH 72 and i doubt i would place any better  :) It seems strange that the limit was set below what was apparantly available in 1973 1974  ???

The Poms class is i believe pre 74 not pre 75  :)
« Last Edit: February 08, 2010, 12:28:12 pm by TM BILL »

firko

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Re: 1973 shock position
« Reply #13 on: February 08, 2010, 12:30:42 pm »
We based our initial rulebook on that of the AHRMA who in turn had taken their suspension regs from the Brits. When I was formulating the first basic set of rules I consulted Dick Mann as to why they'd picked, A pre 75 as the cutoff and B: why 7" and 4" for the limits. He told me that he'd made a bad mistake based on his and his comittees lack of research into what was available prior to the Dec 31, 1974 cutoff. They'd wrongly deduced that most of the bikes comformed with that limit, thinking the LTR Maico and '74 CCM were factory designated 75 models.

They rightly deduced that 1974 was the last true year of the old school suspension but had overlooked the few biikes that had led the suspension revolution being available in '74. This is why the Brits run pre '74 instead. It cuts out the LTR Maico, CCM and others. We've survived 22 years with a system that inconveniences a few but is perfect for the majority. '74 LTR Maicos with their suspension limited to 4" are still competitive and barring a few minor glitches, the systems worked well.

Offline GMC

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Re: 1973 shock position
« Reply #14 on: February 08, 2010, 01:30:13 pm »
Then why oh why is the class restricted to 4"  ??? wouldn't it be equally as simple to have 5 or 6 inches  ???

It seems strange that the limit was set below what was apparantly available in 1973 1974  ???

The Poms class is i believe pre 74 not pre 75  :)

That would be fine if the class was only for 73 -74 models, but it’s not. It’s also for 70 - 72 models.
These earlier models would be further alienated by the more competitive 74 models with longer travel. Everyone would also want to modify their bikes to longer travel and then the class would not represent those early days of 4” travel
While long travel bikes were around in 74, I don’t believe there was that many of them.

As I understand it, the Poms call it Pre 74 but it is for bikes up to & including 74 models???  Maybe some in-house Poms can clarify.

I was also of the understanding that period after market swingarms could run as built but had to restrict suspension if necessary.
G.M.C.  Bringing the past into the future

Shock horror, its here at last...
www.geoffmorrisconcepts.com

For the latest in GMC news...
http://www.geoffmorrisconcepts.com/8/news/