So where do I get a derailer for a moped sized chain? I figure you could make a two speed or maybe three before the chain would be running at to much of an angle. Also a rear sprag would be needed.
Actually a three speed hub like from an old bike would have the sprag already in it, just relace the spokes to your rim and its all good, O-- accept for the rear brakes. Maybe centerpull style like a bike?
I'm leaning tward the three speed hub, those things rock!