Every time someone builds a motorcycle, the question of weight pops up. No matter how light you go, it's always too heavy for someone else. Well, how about 62 pounds?
This home built mountain bike sports a 35cc engine plus:
an 8 speed Shimano hub (Planetary Gearbox) in the back wheel that shifts the gears for pedaling and for the motor, has freewheeling for both engine and pedaling… it can be ‘motored with no pedal movement’, ‘pedaled with no motor crank movement’, ‘pedal assisted when motoring’ and is ‘totally free wheeling when not pedaling or motoring’.
Alexander Kiefer, in New Zealand, wanted something that would get him up the hill as well as down and this is the result. There's also 5 inches of suspension travel and hydraulic brakes. He can ride his favorite downhill courses as before with no car needed. The motor gets him there, takes him up the hill, he shuts off for the down hill run then motors home. Three liters of gas goes a long way. He says a 100 mile day is a breeze.
Link: Al Kiefer