i,m guessing at the controller because if the cart is running fine and then just quits and after 10 or 15 minutes ( cool down ) it runs fine again theres nothing else that would cause this.............i have never heard of a motor doing this but who knows................but if its a stock 275 amp controller thats the 1st place i would look.......its not bad it just can,t handle what its being asked to do.......................................