That's not normal. You should be able to spin the motor by hand without much resistance. I would pop the ends off to see what's going on in there. It not like you're going to void the warranty.When I try turning the motor (disconnected from the axles, so it's not the gearing I believe) I only get about 1/4 turn before some resistance. Was thinking of popping the caps off the motors and seeing what was causing it.