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You don't gear around hp...you gear around rpm. If a certain gear was proper for 40hp...it's still proper for 60hp. Whatever final drive ratio puts you at your max rpm at the fastest part of the track. Fastest part of Loudon is just before you back off for t1...so you'd want to be in top gear about the start finish.

By Max rpm I mean the maximum rpm you WANT to run...not necessarily the factory redline etc.

Exceptions are correcting bad situations...like a hill etc. If not getting up a hill are hurting your lap times more than losing a few mph on the straight...then gear for the hill.

You wouldn't re-gear a bike because of a torque increase unless the modifications that increased torque also lowered the max rpm limit.

If you are trying to move a mountain...you don't use a shorter lever when you get stronger...you use the same size lever and move the mountain easier (meaning quicker lap times).

Gearing is all about fitting as many usable gears into your useable rpm range. Hence the close ratio gearboxes found on race bikes. You don't want to only be able to use 4th and 5th while everyone else is using 2nd, 3thrd, 4th and 5th.

The wider the power band, the fewer total gears in the gearbox you can get away with (more area under the hp graph). That's why GP 50cc bikes with a powerband 2,000 rpm wide had 8 - 12 gears in tranny.

In Frank C's situation...if he had another gear to work with he wouldn't have to compromise his Straightaway gearing....instead of over revving in a low gear up the hill, or bogging in a high gear...he would have a gear inbetween the two.

Use ALL your rpm...and as many gears as you can.
JohnnyB
 
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