Originally Posted by Bikeguy Joe
The rear wheel size does matter...a little, a 24" wheel will have a slightly lower overall speed at any given rpm than a 26".
Except for a friction drive, which drives the outside diameter
of the wheel at a certain speed (not rpm as a sprocket drive does) which would be friction wheel RPM multiplied by it's
circumference. So the tire tread
tavels a certain feet per second,not revolutions per second. And since the tread is connected to the ground, it then travels at the same feet per second.
So rear tire diameter is irrelevant on friction drive.