M/C class ?

[LJB]

After looking at the rules and records, I noticed that there are no records for M-P in any of the CC limits... is this even a viable class?

[JackD]

If you are speaking of a M class bike with an otherwise Production engine, there is nothing to prohibit it but you can't expect to be competitive against the same engine with all the external modifications allowed to the engine in M class.
There is no distinction and hence no separate class.

[LJB]

i got ya... only forwards, no going backwards on the engine distinctions... it is all starting to come clear...

[Nortonist 592]

LJB,  If you look in the rule book you will see a class for modified production.  This class allows a number of frame mods and virtually unlimited engine mods.  To run a modified frame and a stock engine (production) would put you at a distinct disadvantage.  If your engine and frame are not from the same manufacturer then you go to A (special construction).  If you want to run production then your frame (rolling chassis) must be as it came from the manufacturer with the exception of the allowed mods. and the engine must be stock appearing on the outside.  The neat rule in production is "any performance modifications must be out of sight".  Good luck.

[LJB]

My race bike as it sits right now is a production motor, but, is an stock OEM off-road frame which is not legal in production, yes?

I did not see any real clear verbage of how the frame and motor classes all meshed... I think I got it now... maybe...



 

[Seldom Seen Slim]

Rulebook, Section 7.E.:

7.E.1   PRODUCTION
A production motorcycle model of which 500 or more have been produced and which are available for sale to the general public through retail motorcycle dealers and is completely equipped with full lighting equipment, frame, forks, wheels, brakes, gas and oil tank (if O.E.M.), fenders and seat. 
The motorcycle must appear identical in all respects to the production model it represents, including the intake air box and exhaust system. The exhaust system, looking at the end (down its centerline) shall be unmodified, i.e. the exit diameter of the canister (muffler) cannot be enlarged. This comparison will be made when the bike is assembled as ready to run. Any performance modifications must be out of view.

There -- that's a cut-and-paste from the rules.  Not much ambiguity.  The way I read it -- an "off-road" bike might qualify under the 500+ produced part of the rules, but you might have trouble with the lighting part if your bike doesn't have any.  I'm not a rule interpreter -- I just read 'em.  You might ask an official for clarification.  Try Tom Evans -- his number and email addy are in the book.

[JackD]

I thought the wording in the Production Class looked familiar.
I wrote it to the satisfaction of the entrants in 1980 and it actually tightened up the class a bit.

[LJB]

...Not much ambiguity.  The way I read it -- an "off-road" bike might qualify under the 500+ produced part of the rules, but you might have trouble with the lighting part if your bike doesn't have any...

not too much ambiguity...

 


i will give Tom a holler and see what he says.

[LJB]

I thought the wording in the Production Class looked familiar.
I wrote it to the satisfaction of the entrants in 1980 and it actually tightened up the class a bit.

when you wrote it, did you intend for Production to be a mass produced class or a mass produced class for STREET bikes?

to further complicate the matter, if the off-road frame is specifically designed for MX/SX use, does that make it a RACE ONLY frame?   
 

[tortoise]

The exhaust system, looking at the end (down its centerline) shall be unmodified, i.e. the exit diameter of the canister (muffler) cannot be enlarged.

Would I be correct in guessing that if the exit diameter is not enlarged, internal muffler modifications are acceptable, and routinely made by competitors?

[Seldom Seen Slim]

You'd be correct in guessing, but i don't know if you'd be correct in fact.  That is, I hear that well-designed mufflers don't have all that much restriction.  We all know about the squid that removes his muffler and replaces it with a noisier one, "knowing" that it'll make his bike have more power.  He doesn't rejet, doesn't dyno, and wonders why his buddies now leave him out of every corner.  But it does sound cool.

So to get back to your specific -- some racers do "gut" the muffler cannister, and as long as the result looks 100% stock -- you're in.  But that means -- and the rule states -- that things like the inner parts that you can see when looking down the outlet of the muffler had better look just like they did before you went to work inside there.  Restrictors, spark arrestors, cross-braces, etc.

[JackD]

From the first days of the Production class with AMA it was always meant to be applied to a bike that was originally street legal.
The modified bike class was always intended to include non-street legal bikes , Road Racers, Dirt bikes and bikes that have been modified from Production.
Class A was intended to welcome all comers with the fewest configuration limitations and with that presumably the fastest speeds for an open bike.
Right now there only 3 bikes in the World that take full advantage of the Class A rules.
One was run in 71, another is just finishing up, and the third is under construction.
Bastardization of the rules has led to the confusion you are the victim of today..

[tortoise]

Right now there only 3 bikes in the World that take full advantage of the Class A rules.
One was run in 71, another is just finishing up, and the third is under construction.

Would you be willing to expand upon this? I'm picturing a rear-engine laydown layout like a streamliner, but open. A scary thought.

[JackD]

As far as the Production pipe is concerned. it has been a popular practice to replace double and thick wall OEM tubing with material that is the same OD but a larger ID to increase the flow.
Foreign made bikes that are street legal also might be different than what is offered in LA.
Anybody with a Canadian 350 Yami knows the difference.

[JackD]

Right now there only 3 bikes in the World that take full advantage of the Class A rules.
One was run in 71, another is just finishing up, and the third is under construction.

Would you be willing to expand upon this? I'm picturing a rear-engine laydown layout like a streamliner, but open. A scary thought.

NOPE, you will see them soon enough and if they satisfy you they work, you can do it too.
Recumbent petal bikes have a very dedicated following don't they, the 3 that I am speaking of are better ?

"Timing is a real important part of rain dancing."