[ryaneogilvie]

Im pretty sure (you can check the wattage) You can get more power by using the dual motor mount for versa-planetary with two 775's if it fits with your setup.

Assuming that your key is shearing you may try finding a key made of stronger material that wont shear. you might also be using the incorrect key in which you should find the correct one. ( the correct key should be a press fit in the keyway of the motor).