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.