Sorry if I wasn't clear, but a Novak 5.5 ( around 7400 I think), I am running it on a Reedy 4800mah 2s lipo, and the gearing is 18/84. The gearing does not seem to be the problem because i have tried raising and lowering the pinion size and it does not help. I have run this car off of two mamba max's and they both ran hot. This motor ran fine on the GTB and My XBR and 8.5 never ran hot.

The only thing I can think of is something is binding, but i have checked and rechecked the bearings and my diff shimming and gear mesh's and they are all fine.

I REALLY do think it is the mamba's, because they are both fine, just run hot on that particular motor.