Originally Posted by X men
Checkpoint $$ or can anyone recommend a good motor ?
Go with a 112t spur and pinion sizes 32-35t. Unless its one of the super duper torquey motors, or you're accustomed to riding on rims, you shouldn't need a 36t.
For smaller tracks (less than 100ft straight) and tire sizes between:
* 59.5mm & 60mm use the 32t
* 58mm & 59.5mm use the 33t
* 57mm & 58mm use the 34t
For larger tracks and tire sizes between:
* 59.5mm & 60mm use the 33t
* 58mm & 59.5mm use the 34t
* 57mm & 58mm use the 35t
The target rollouts I've seen have been anywhere between 31mm and 33.5mm, depending on motor torque and track size.
If you use a smaller spur than 112t, the torque from the motor will strip even the hardest of spurs in a hard crash, due to less surface area contact between the spur & pinion.
Also keep in mind that if the brushes are sprung too soft or you have the motor geared too low, then it will heat up easily and *seem* as if you are geared too high. I always try to stiffen the springs, before going to a smaller pinion. The brushes wear down kinda fast and you'll need to shim the springs every 3 to 4 runs.