Mounting the BAFANG motor is easy. The whole unit simply slides into the bottom bracket shell and is fastened into place with the provided hardware. Here again, you will need a special bottom bracket tool for this job. I would recommend purchasing the tool directly from BAFANG with the motor. It cost about $20.
A word of caution! Pay attention to the torque on the bolts mounting on the motor. The motor case is aluminum and can easily be stripped if over tightened.
Next, I installed the chain ring, crank arms and pedals. Take care to make sure you mount the crank arms on the correct sides. While they look identical, there is a left and right arm. If you get this step wrong, like I did, you will need a crank puller to get them back off. So, take your time and check the markings on crank arms before installing them.
Ken Whittaker