All brushless motors from Novak will be sold with sintered rotors from now on, so... legal or not, they are on the way.
The sintered rotor is a 5-minute swap and direct fit in all motors between 3.5R (which it already has stock) through the 7.5. The endbells and cans are identical and need nothing but a hex driver to remove the endbell.
The older 4300 (now the 10.5) and the 5800 (now the 8.5), as well as the 13.5 stock motor, needed an upgrade kit with a new endbell with larger bearing to install the sintered rotor. The new 8.5, 10.5 and 13.5 motors already come with the upgrades on them.
The stock clear plastic fan is a little fragile and doesn't push a lot of air. Nexxus Racing, Team Much More and even Novak sell stronger 30mm fans that are direct fits and push more air. If you're running a 5.5 or faster, you'll probably need a fan in the car. I use one in my BJ4WE with a 5.5.
A sintered rotor will run MUCH cooler, and if you run one, you probably won't need a fan on the motor. If you are experiencing heat issues with the motor, you are either over geared, or over motored. You could also try the finned motor heatsinks from Novak, if all else fails, but in an off road car, you probably would never need that.
doug
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