AMA rules for "A" class engines

[tortoise]

In the AMA Supplemental Regulations for the BUB meet, we read that special construction motorcycles may have. . .

Any combination of engines, not to exceed two are allowed.
Combined engine displacement cannot exceed maximum of
3000cc.

Conspicuously absent is the word "motorcycle" before the word "engines", unlike the SCTA rules. Is it OK to run other than motorcycle engines? Have any shown up and been allowed to run?

[Seldom Seen Slim]

Well, Denis Manning's motor in the #7 'liner was a one-off, so isn't strictly a "motorcycle" engine -- wasn't sourced from a bike, except that it was purpose-built for a motorcycle.  This particular situation has been chewed long and thoroughly here before, and I thought I'd bring it up just to liven the day a tad.

[tortoise]

Well, Denis Manning's motor in the #7 'liner was a one-off, so isn't strictly a "motorcycle" engine -- wasn't sourced from a bike, except that it was purpose-built for a motorcycle.  This particular situation has been chewed long and thoroughly here before, and I thought I'd bring it up just to liven the day a tad.

I'm asking about the AMA rules, not the FIM. In particular, I'm thinking about the pushrod classes, which don't exist in FIM.

(You raise an interesting unrelated question, though. Where, precisely, in the FIM rules does this "motorcycle engine" requirement appear?)

[Seldom Seen Slim]

Ah, I see -- said the blind man.  I'm not a Bub's event racer and therefore don't pay close attention to the difference between the FIM and AMA rules -- at least not close enough to have seen the inherent error in my response to you.

As for the FIM rules and if (or where) they state a motorcycle engine rule -- I attempted to understand the FIM rules in early '07 and decided it wasn't in my best interests to follow through on the attempt.