Here it is.
http://www.chiefdelphi.com/pics/bin/107542728548.jpg Sorry it isn't more "revealing" but the jist of it is the shafts of the two motors have been pressed into either end of a machined aluminum slug, and the aluminum U channel that they're mounted on is hinged. There is a threadded stud that pulls the U channel down, and the aluminum slug that is pressed onto the motor shafts is forced down on the wheel. When the motors run, the aluminum slug rubs aganst the wheel, and spins it. It's a very crude system, but it works surprisingly well. However, there are some inherent problems: If you don't apply enough pressure on the slug, it will slip on the wheel and take chunks out and/or melt the wheel. If you apply too much pressure, you could hurt the CIM motor's bearings. Because of the fact that it is a FRICTION drive, it looses alot of energy as heat, which gets dissapated by the frame. Also because of the constant deformation and wear on the wheel, I go through one every 15 charge cycles or so. - Rotating the wheels every few cycles helps prolong their life.
As for speed, it zipps along - I used to ride it to and from classes, but my school's administration banned me from riding it inside - The excuse "It's a Tech. project" wore off really quickly (I think they're jealous).
