Hey guys and gals. For years, I have been running the castle sidewinder and 5700kV motor in various rc's. when checking the temp of the motor though, do I check on the can or the end bell? I have been checking on the end bell and it is 20 degrees higher than in the middle of the can, but I have been gearing o the end bell temp. I am currently running a 22t pinion and an 84 tooth spur in an AE t4. my temps after about 10-15 minutes on high speed test runs or a 4 minute race are roughly 175 at the end bell, 155 in the middle of the can and the ESC is 150 or so. Castle has told me these are acceptable for this system, but i still get a little nervous. My battery is either a 4200 25c 2s or 5000 20-30c 2s lipo. yea-nea?!?

Well, if castle says its okay then stick with it and when motor fries, demand a new one I always check temps on the can but gear for lower temps (around 100-120) but your gearing on the T4 is a bit steep considering the KV of your motor!! You could bump that pinion down to an 18 or 19t and you would still have all the power needed and a bit more torque

Your esc temp is awfully high. I usually only let mine get to 125 max.

On a 2wd truck, I usually go off the end bell for temp simply because you cant really get to the can with my temp gun, but on a 4wd I go of the side of the can.

It's best to check the temp on a non-shiny surface of the motor can if possible, like a sticker. I agree that your temps on both motor and esc are slightly high, but not dangerously so. I'd try dropping 1-2 teeth on your pinion to see if they don't come down a little.

Castle motors are OK at higher temps than other brands, like the Castle folks said. I do not know about the esc though. Apparently Castle said that was OK too. I believe that where ever you get the highest temp reading from is the place or temp that you should use as your guide, so use the end bell in your case. I wonder if changing out the bearings to a set of ceramic bearings would help? It would be a good experiment.

The infared temp guns do not read accurately off of shiny metal. Spray a little black paint on the can, or stick some tape on the motor and read that spot for a better reading. The farther away you have the temp gun, the larger the area that is looked at and averaged to get your reading. Your gun reads a larger spot than the little red dot. 8 inches away might be a 1 1/2" circle, so hold it close.

Also, I agree with those above who recommend a smaller pinion. You must be flying! I think your motor and esc would run a little cooler, and I personally would like the better acceleration. If the acceleration is too much, you can tune in some punch controll.