SPC Racing

what is the smallest comm size you can go with a stock motor

Jon Kerr

iTrader: (17)

With pretty much all standard size comms (not the Reedy KR or quad mag motors. They use a large comm.) you don't really want to go much farther than about .270" I've pushed it to .265" and paid for it. They start burning brushes really bad, ecpecially if it's a laydown motor ot P94 even because the brushes always have the comm shorted out.

Tek Nickal

It just eats your brushes and gets the motor really hot and the comm gets all black.

Mike Haynes

iTrader: (2)

I stop racing them at .272 but use them in practice as long as they work, just have to narrow the brush face, but the small arms arn't as fast.

Tek Nickal

If you have a slower motor for practice, then you don't know how to setup your car properly when the motor is faster, so you'll have your setup messed up. Having a good motor in practice is just as important as having a good motor in the main.

True R/C Racing

in Stock i use my racing motoe as practice as well. Just cut comm before Main seems to work Well for me