8XL running slow

I did take the Airtronic MX3 redio off and put the original traxxas one on and it performed the same. I did not check the controller or motor temp being it only ran for 1-2 minutes. Is there a way to check the motor to see if it is bad? Is it unlikely to be the controller? I will put it back together, recallibrate the radio and check the EPA. Then I will check the temp. Any further suggestions? Thank you all!

[zeropointbug]

Maybe try doing a free wheel test first... 70% thottle for a couple minutes to see how things go, check temps, then report back. Okay?

Also, do you have any other controllers that you could test it with?

Great advice. No other controller, just the 12020. I will put it together and do the 70% throttle test, take a temp and report back.