[slimthelineman]

Also for a given motor going up in voltage will increase temps regardless of gearing from my experience. You will just plain make more power. The only way to offset this that I know of is to go down in kv as you go up in voltage. Keep your target rpm the same by varying the two and your temps will go down. The 2650 can be run on 6s but it's impractical for anything other than speed runs. Most guys I race with that ran that motor were in the two to three cell range. It's hard to tell with gearing without knowing the internal ratio and driving style. I find that driving style will vary the gearing by up to two teeth. I would say gear it as low as you can and keep an eye on temps until you can get a hold of some 3-4s batteries and or a lower kv motor.