Do others agree that as flat slides (to the best of my knowledge) were available in 77 therefore they should be legal post 75 classes??
Hi Dave. I am Mark Boddy. We met at the 2008 Classic Dirt Track Nationals and I was one of the Scrutineers.
I was PCRA's eligibility guy for New Era from it's establishment through to the end of 2007.
I was coached by Marcus deCaux on eligibility issues and have been involved in some eligibility disputes at National open meetings.
I have successfully protested a bike on eligibility grounds.
Historic Road Racing rules consider the Carburetor to be a major componant and therefore it must be of the same Era of the bike.
Why should Classic MX and Dirt Track be any different?
The original intent of the flat slide rule can be determined from past versions of the MoMs. (In 1977 Pre-75 was the newest class).
For example,
16.11.4 b) Carburetors
i) Any round-slide carburetor can be used.
ii) Modern flat-slide carburetors are prohibited.
iii) Early flat-slide carburetors (Walbro, Lectron etc.) are allowed provided the owner can prove that they were available pre 1975.
What happened was that it was not possible to prove that the Lectron was available pre 1975 because it was not available until 1976.
So the rule was changed.
In 2000 Pre-75 was still the newest class and the rule was:
14.2.6.2 Carburettors
a) Any round slide carburettor of a type manufactured within the period specified for the class in which the machine competes. For Pre 1960, 1965 classes the Mk 1 Amal Concentric may be used.
b) Flat slide carburettors are prohibited.
c) No reed valves ... etc
d) From 01/01/2001 no reed valve ... etc
For 2002 Pre-78 was added to the MoMs. But only the most minimal changes were made to the Classic Motocross rules to incorporate it.
This is the root of the problem.
The carburettor rule was updated again:
14.2.6.2 Carburettors
a) Any round slide carburettor of a type available Pre 1975 may be used except the Pre 1960 class where a Mk 1 Amal Concentric or period carburettor may be used.
b) Flat slide carburettors are prohibited.
c) No reed valves ... etc
It seems to me that the change to the carburettor rule was made independently to the addition of Pre-78.
What other reason would there be to exclude round slide carbys from 1976 or 1977 from Pre-78 bikes?
The general precedent of rules in the MoMs is that Era parts are allowable in the Era. This oversight is inconsistent with this.
For the next year (2003) a serious attempt was made to add Pre-78 to the MoMs.
Pre-78 was given it's own eligibility section:
14.2.13 Pre 78 Classes and Eligibility
...
These detailed rules contradicted many rules that appeared before them in the MoMs. For example, 7" suspension travel limits, etc.
It is clear when reading the 2003 MoMs that these rules applied to Pre-75 and 14.2.13 applied to Pre-78.
This should probably have been explicity stated in the MoMs but was not.
Later Evo and Pre-85 were added each with their own Eligibility section.
If you do not believe that this is the intention of the rules then how do you explain the rationale for a pre-75 roundslide Mikuni to be fitted to a 1980 IT175G before it is allowed to race (it had a 32mm powerjet Mikuni) or to have to fit a Mikuni roundslide to a Pre-85 RM Suzuki to replace their Mikuni TM?
This is obviously nonsense.
So what carbies can be used?
This is a list of some common carbies and their availability date:
Lectron (non powerjet) 1976
Lectron powerjet 1979
Mikuni powerjet (roundslide) 1979
Mikuni TM 1982
Keihin PJ 1985
Mikuni TMX 1987
Keihin PWK 1988
Mikuni TMS 1992
Mikuni PM 1998
Keihin PWM 1999
Therefore as the flatslide Mikuni was not available in 1977 it cannot be used in Pre-78.
The MoMs should NOT be amended 'to allow flat slides for Pre-78 and later'.
Instead it should be amended to explicitly state that all eligibilty for Pre-78, Evo and Pre-85 classes is stated in the individual section for each of these classes.
Mark Boddy
