Removing the sub-gear to save weight
 

Anybody ever done this? For those who don't know what I'm referring to, the sub gear is right on top of the primary gear as shown here.
Attachment 27687

Looks like it's only function is to ever so slightly dampen the engagement of the primary drive gear to the clutch outer, and maybe make things slightly quieter. It would seem this is totally useless to me and is dead weight spinning... What do you guys think? Also if you did remove it, did you need to add a spacer where it was? or does it not need one?

Nobody? Alright well it's gone. I'll let you guys know if I notice anything.

It is there to quiet a straight cut gear set. They run a straight cut gear set because they are stronger. They could run a quieter gear set, but they take up more room as the gear contact goes down. I would imagine that there is a potential in friction savings here as well. good luck

It is my understanding that those are for gear backlash, RC51 owners as far as I know remove the ones similar to them on there gear driven cams to lighten the valve train.

Maybe RCVTR can chime in to confirm.

I installed my Factory Pro shift kit and ignition advancer today and there it was. Other than noise reduction, it may have been there to reduce harmonics caused by gear lash. At low RPM a V-twin must have crank speed variations during each rotation. But given the strength this gear must have to transfer power to the clutch, I decided to remove it. Runs and sounds fine, I to will let you know if I notice any thing down the road.

Thanks, I removed mine as well, let's hope for the best! lol

Any confirmations on hp gains?

Did you happen to weigh the rotating mass that was removed?

James

I just bought a scale. I will weigh the parts tomorrow for ya.

I did a small write up on the sub gear here.

I honestly can't tell a difference in sound or performance. However, I know that half a horsepower (just a wild guess) is there! :)