Pinion selection

[treaves]

O.K., as I'm new to this, when it comes to what motor and pinion to go with, I've just been looking at the combination's people are using. So I figured I should know: what goes in to selecting which pinion to use with which motor?

I realize that the different motors will have different RPM's, and therefor require a different pinion to achieve a particular headspead. But what is the relation? IS there a generally accepted formula? And how do the mAh of a battery play into this?

Thanks!

[Team-MAYHEM]

Battery Voltage x KV of motor x # of teeth on pinion x % of efficiency of motor / main gear teeth...

Example of 600 with a Hacker A50-14S:

37v * 550kv * 18T * 85% / 153T = 2035 rpm (mine is actually 2050)