I like your thinking, but... bicycle wheels, (bearings) are not made to tollorate the weigt, torque, and rpm's of a moped. The issue with tires is weght load limit, and speed rating. The deraulure and gears idea would be awesome, however, I'm afraid that it would get torn up. How about one of you evil geniuses make an internal 3 speed Hub that is beeefy enough to handle some HP's.? We could all be doin 60mph, and getting there quick.