revo motor

[mach1stang]

hey guys, a buddy of mine is building a e-revo, but he wants to run 12 cells, he is wanting to a 9xl, but i think he could better performance out a higher kv motor while still running cool what would be his best performing motor on 12 cells, he is looking to go around 40mph?

[Purplefade]

mach1stang, about the best advice I could give your bud would be the advice the guys have me when I asked a similar question. Simply calculate the KV of the motor by the voltage you'll be supplying and shoot for about 35K rpm out of the motor, that said, 12 cells: 1.2v per cell * 12 = 14.4v so I would guess you'll be looking at something like an 8XL, maybe the 7Xl if your looking for blinding speed, but be VERY Carefull of heat on the 7 as it has a tendancy to run very hot.

That said, either motor would benefit greatly from Mikes Motor Clamp Heat Sync, almost a necessity on the XLs

As for speed, use BrianG speed calc to figure out your spur pinion combo to get you where you need to be speed wise.

Best O'Luck!

[lincpimp]

the 8 or 9xl would be a good choice seeing that he will be using nimhs. Keep in mind that unless those are new high quality cells that you may overheat the whole combo. Most nimhs can't keep up with a good brushless motor, the amp draw is too much for them. I would try the 9xl and gear for about 30 mph. Not sure if you will get 40 out of 12 cells, not without alot of heat. definately use the motor clamp/heatsink, it is a must have. Will he be using a emaxx tranny or the stock 2 speed revo tranny. The 2 speed may help with temps as the lower 1st gear ratio will take some strain off the motor.

[Soya]

I use a 7xl on 12 cells on my revo, works well, things are warm but nothing too hot.

[mach1stang]

i will be sure to tell him.