How does the peddle assist work? Is it just on or are there multiple levels? They're looking really appealing at that price especially since even on closeout the updated version of my bike is about 1300 shipped. http://wheelworld.com/m/product/izi...VUD4U4Csa-SUioQs8QMVvUnZjNl3C2SwXgBoCr7Lw_wcB But that thing would be perfect with its lithium ion battery and twist throttle on top of the pedal assist. My current bike will do 10-15 miles still so I think I can squeeze one more year out of it.