I'm Having a complete Blast with the 1/10 scale motor/speed control system on this little truck. There is No Way i'm removing this 1/10 scale system from this truck, doing 40+mph on 1- 2s lipo over rough terrain is a complete blast. Personally i feel the stock motor is a little under sized for this truck and when the summer time hits, its going to really show with high motor temps. I had an extra mamba 7700 motor and speed control sitting around so i installed it, the power and speed is great!!! I turned down the setting on the speed control so the added power of the 1/10 scale system would be easier on the drive train, haven't broken anything so far. Getting 40 + mph on 1- 2s 2200mah lipo with 9-min of run time with regular driving, with 14.8v installed getting 54 + mph with the throttle about 60% used. With this kind of speed it Feels like i have an e-revo inside the summit's body LOL!!!! 50t spur with an 14t pin is my set up. using the motor mount from tenbol.com http://s1109.photobucket.com/albums/h435/dishun71/