gearing and size of the commutator
 

If a motor is brand new, does the size of the commutator play a factor in the gearing, as opposed to when it is skimmed a lot but still in good shape?

The reason I ask is because I have been given a good ratio for a track, but wonder if I should take into account that the monster stock based motor i'll use is brand new and therefore the comm is of a bigger size than usual.

I doubt it is a factor,but thought I would check as ive never seen it asked before :)

Im guessing the size of a new comm doesnt make any difference to a well skimmed one in equal condition then? (being the same arm).

Makes NO difference bro! Good luck.;)

cool, I wondered why it hadnt been discussed before. Hopefully you can understand the logic for asking though, 1 full turn of the arm will obviously be less the more its skimmed, the only thing I guess that changes is torque and rpm...

And this is what can factor the gearing anyways...

If I had a brain, id be dangerous sometimes :lol:

Actually I totally understand your question and it made me have to stop and think.:weird::lol: But your final roll out will not change as the commutator size doesn't effect roll out. However like you mentiond, it will effect your torque and rpm to a certain degree. Also your choice of spring and type of brush will change your torque and rpm, so you can adjust accordingly to your application. But overall, not a bad question to ask dude. :)

The smaller the comm, the more brush wrap you have and the more rpm the motor will produce.

SerpentD- Exactly- It made me stop and think, as we use rollout or final drive ratios to calculate car performance, but didnt take into equation the size of the comm (but as you say it doesnt affect the gear ratio) i'll be glad when I go brushless, questions like this wont be popping into my mind hehe

CCristo- Yes, brush wrap changes the rpm band, i'm glad i'll be rid of that too :D