Originally Posted by gigaplex

Depends on the enamel type used. Hobbywing recently changed to a high temperature enamel that can do 220C, but there are types that fail around 105C (220F). I'm not sure what the typical rating is for most motors on the market right now.

If the stator wire is going black, that's the enamel discolouring, not the copper. Copper can handle way higher temperatures. The rating is generally what the insulation can handle.

As for the motor reaching 250F, don't forget that the motor isn't at a uniform temperature. The windings can be hotter than the can or the temperature sensor on the sensor board.

Originally Posted by OffRoadJunkie

I'm not a motor engineer. I just like to run their numbers.

So, let me ask this question. The purpose of the enamel is to protect the winding from shorting out on each other. So, discoloration, of the enamel, should not affect the resistance and/or performance of the motor. Only deterioration, of the enamel, will affect the performance, but at that point, the moto will be shorted and not work. Is this accurate?

Originally Posted by billdelong

I no longer race 1/10 stock classes anymore, but the Texas summers are brutal on stock electronics. I had to gear up to be competitive and had 2 fans on my motor to help give it a fighting chance, but I generally saw performance fade between 6 months to a year of racing. Yeah I could probably run my overworked electronics for many years on end, but it would put me at a disadvantage running aged out electronics. I pay a lot of money to play with toy cars so I want to make sure I have the best advantage possible when I race

Originally Posted by gigaplex

How hot are we talking in Texas? Melbourne where I race gets pretty toasty too, high 30's and occasionally low 40's (or high 90's, low 100's in freedom units) and we make do.