The physics of the bicycle

Nature : Although bicycle design has remained relatively unchanged since the early 20th century, cycling’s recent resurgence in popularity has prompted several innovations in materials and technology. One example is the inflatable frame developed by the Ford Motor Co so the bike can be easily transported in a car or bus. Another is the redesign of a recumbent bike—the rider lies chest down—to improve its aerodynamics. Also being considered is rear-wheel steering, which would improve efficiency by allowing the chain to be shorter. To better understand the physics involved in bike design, Nature‘s Brendan Borrell looks at a brief history of bicycles and the physical and mathematical forces that keep them upright and propel them forward. Borrell also mentions the “father of modern bicycle theory,” David Jones, whose article exploring bicycle stability appeared in the April 1970 issue of Physics Today.