Here's a short primer to the Chinese built in-frame bicycle motor kit. 50-70cc piston ported (old, old school) two stroke. Dry plate clutch (like a car), single speed transmission. 1-3 claimed horsepower. 25-45 mph top speed. (not recommened for the faint of heart) Can be operated comfortably from 10-25 mph continuously. 100-150+ mpg! Can be mounted on a suitable bicycle in 4-12 hours, depending on how thorough you are. Adds about 20 lbs. to the bike. Anybody want to add anything before I lock and sticky this thread?