So you're replacing your Honda CB charging rotor, with a nice shiny new RaceTech Electric F901? Excellent! Now, don't forget your rotor puller to complete the job. The use is very simple, Once you remove the locking bolt, you thread in the RaceTech Electric rotor puller, and give it a tap with a hammer. The rotor will pull right off the crankshaft, leaving your threads in perfect shape. Don't do the job without it!