Bring a Production Engine to class size (Bike)

[rouse]

There comes a time when the kid needs to listen to the father.

The key sentence in the book says in effect " Any performance modifications shall be out of view."

If you can't see the innards of the engine when you look at the bike then that part is out of view, simple.

Rouse

[grumm441]

There comes a time when the kid needs to listen to the father.

The key sentence in the book says in effect " Any performance modifications shall be out of view."

If you can't see the innards of the engine when you look at the bike then that part is out of view, simple.

Rouse

What he said
G

[Koncretekid]

Along the same lines, would it be legal to de-stroke a stock motor to make it into a smaller class?  I've looked at several bikes, like the 650 BSA, which are just a few cc's over the limit.  The BSA is 654cc.  I think that just grinding the stock crank undersize on the high side (shorter stroke) would do it.  Would it be legal in the 650 class?

[Seldom Seen Slim]

It'd be fine - as long as you're not in a production class.  The production engines must run in the same class as the engine would run when completely stock.  In other words, for instance, our ZX14 started life as a 1352 cc.  Boyoboy would it have been easier to get rid of a few cc to get under the 1350 top limit of the next lower class, but since we couldn't - we had to bore and stroke o get it closer to the 1650 top limit of the class.  And while that was okay for a year or two, Kawasaki then upped the base engine size to 1441 cc -- giving more room to bore and stroke it to lots more than that 1532.

But anyway -- in production the bike must run the same class as it would with an unmodified engine.

[BVCBR]

As SSS stated, that bike (BSA) would have to run in the 750 Production class. The rule states; "OEM engine displacement determines the displacement class for competition." The Honda CBX 6 cylinder is another example. It's OE displacement is 1047cc, it would have to compete in the 1350cc Production class.

If you want to be competitive in the Production classes you have to follow the saying; "choose your weapon wisely."

[rouse]

; "choose your weapon wisely."

That's what she said

Rouse

[fredvance]

The early ZX14's were 1353cc, have to run in 1650 P/P. They didn't want to run in 1350 production anyway

[Seldom Seen Slim]

Fred, I forget -- when's the last time I called you a smart-a**?

[fredvance]

I resemble that remark!!