Flywheel Bike

very cool concept

There was a flywheel design used in city buses , where the flywheel would be spun-up while siting at a traffic light by overhead power sources at every stop .

This system was actually used quite successfully for years . THE FLYWHEEL BUS IS BACK - Access to Energy Newsletter Archive

There is a guy who builds all kinds of vehicles from scratch, an actual genius really, and among those different vehicles made a couple MBs from the ground up, frames, drive trains ect. that were the most innovative I've ever seen. He posted a little on the other site back a couple years but generally doesn't bother with forums. The last project he talked about and in the planning stage was a motored bike using a Honda or Subaru 35cc to power the bike and charge a flywheel as well. Definitely in front of the curve.