Depends the width of your motor, with my RCM motor mount and my NEU-Castle 1520/1Y I can gear down to 12, maybe 11 but I am not sure. Under that, the motor hit the rear chassis reinforcement.
Inferno VE MMv3 NEU-CC 1515/1Y 4S "Flying machine"
Can any light modding be done to get to 9T or 10t? I borrowed an RCM mount from a friend. Going to see what I can figure out. I'd like to get to 9T if I can since I have one already.