Originally Posted by
smirkracing
thanks for all the comments.
I am still not getting a clear answer to the basic question, which is this: how should I evaluate the following two choices?
-3000kv motor with a 15 tooth pinion
-5000kv motor with a 9 tooth pinion
(both motors running on 2s)
Both setups will get to the same top speed (at least on paper - and that's good enough for our discussion here).
The main thing I want to optimize for is heat - which set-up will run cooler? The one in which the motor spends most of its time at 45k RPM, or at 25k rpm?
The higher KV motor has less turns to make more rpms at the same voltage as the other motor. That also means it has less resistance and can draw more amps.
Like mod vs stock on a track. Stock 17.5 can't make a triple coming out of a tight corner, but in mod with a 7.5 the triple is no problem. You still gear down the mod motor, but the speed is higher and the acceleration is a lot higher as well.
With your example of regearing the faster motor the acceleration should be MUCH higher to the same top speed. It comes down to less turns = more amp draw and more rpms at the same time.