I think that the terms "riding a motorcycle" and "driving a car" are direct transfers from the analogous modes of nonmotorized transportation; that of riding a horse and driving (in a) wagon, and that the distinction in use between horse and wagon is that the driving referred to the horse the rider in the wagon was driving. One rides a horse by being carried; one drives a horse pulling a wagon by providing the signals necessary to get the horse to pull the wagon in the direction desired.