I have a team checkpoint 13.5 sensored motor in my rt5, and my novak gtb took a dump and stopped working. I am wanting to race this weekend and i wont have my new esc in time, so my quesiton it my buddy has a castle sidwinder its sensorless will it run my 13.5 sensored motor with out hurting it?

I believe that the castle will not run your motor. I have been told that sensored esc's will control both sensored and sensorless but a sensorless esc will not run a sensored motor.