Bikes, without motors and with motors.
So in the late seventies I worked at Big Sky Cyclery in Missoula Montana. These were the days when mountain bikes were just being discovered. You could not buy a mountain bike, you built them. This sort of what they looked like.
Homage to the hobo bike. Functional with major style points.
A little mechanical advantage never hurt... Right?
Here's full on motorized bicycle. Hazards of the pedal to the metal evolution.