Originally Posted by Unsullied_Spy

IIRC, adding voltage makes the amp draw go up unless you gear down. If you want to run those 40 series wheels with stock gearing on 4s try it but check those temps. If your ESC fan is coming on a lot, motor is getting too hot too fast, and your lipos are heating up beyond the safe limit (I consider 120 at the shrinkwrap to be the absolute hottest you want them to get) then you need to drop a few teeth.

Stock gearing, 6s lipo, 40 series, and WOT through grass you'll cook it in a matter of minutes. This may sound a bit complicated at first, but you've got to get your gearing dialed in a bit before you'll have the best reliability. On 4s lipo and 40 series I'd aim for about 35 MPH and keep temping it and go from there. Then you can step up to a 5s setup if you want more speed. Those wheels/tires weigh over a pound each so you're going to lose a lot of performance and I expect the lifespan of the differentials will be greatly reduced.