How much play does the shaft have? The ones I have here with the 1/8" shaft have a lot of play and that's not good. I guess the place you bought it from knows what they're doing and sent you the correct motor. The factory just started out bad in my case
. I'm waiting for the correct 5mm shafted motors to come in and I'll definitely pair the controller with them. The black motor looks nice, I'll ask the factory if they can make them blue for me
.