Some of my favorites:
Mankind has invested more than four million years of evolution in the attempt to avoid physical exertion. Now a group of backward-thinking atavists mounted on foot-powered pairs of Hula-Hoops would have us pumping our legs, gritting our teeth, and searing our lungs as though we were being chased across the Pleistocene savanna by saber-toothed tigers. Think of the hopes, the dreams, the effort, the brilliance, the pure force of will that, over the eons, has gone into the creation of the Cadillac Coupe de Ville. Bicycle riders would have us throw all this on the ash heap of history. ~P.J. O'Rourke
Nothing compares to the simple pleasure of a bike ride. ~John F. Kennedy
The sound of a car door opening in front of you is similar to the sound of a gun being cocked. ~Amy Webster
The hardest part of raising a child is teaching them to ride bicycles. A shaky child on a bicycle for the first time needs both support and freedom. The realization that this is what the child will always need can hit hard. ~Sloan Wilson
When man invented the bicycle, he reached the peak of his attainments. Here was a machine of precision and balance for the convenience of man. And (unlike subsequent inventions for man’s convenience) the more he used it, the fitter his body became. Here, for once, was a product of man’s brain that was entirely beneficial to those who used it, and of no harm or irritation to others. Progress should have stopped when man invented the bicycle.
Elizabeth West, Hovel in the Hills