Physics and Bicycling

Combining my work and hobby, I've spent some time investigating the physics of bicycling.  Did you know that to turn a bike to the right, you actually push the handlebars to the left? And contrary to the beliefs of most physicists, the stability of a bicycle has little to do with the angular momentum in the wheels.   I've written a nontechnical summary, and a technical tutorial paper on the bicycle steering. The calculations in the paper were done in MathCad, and can be downloaded.

I've also spend some time exploring the effects of stop signs on bicycle commuters.  Maintaining the same speed on a road with stop signs as one attains on a road without stop signs is very demanding.  For example, on a road with stop signs every 300ft (100m), 500watts of power will result in the same speed as 100 watts would get on a road without stop signs.  Since 500watts is far higher than all but racing cyclists can produce, bicyclists on road with stops signs must slow dramatically.  These calculations were verified with road tests on California St. in Berkeley, a designated bike route with many stop signs.  More details are in this nontechnical article.  Some of the calculations omited from the article are at this link.

People occasionally email me with questions about bicycling and motorcycling physics.  Some of the questions and answers are at this link.

Occasionally, I give a public lecture on the physics of bicycling. Here are the notes from the lecture.

Perhaps the most important article on the physics of bicycling was written by David E. H. Jones and published in Physics Today in 1970 (The Stability of the Bicycle 23 p34-40.)  For those who do not have access to a physics library, the article is posted here (Warning…the file is almost 9MB.)   Eventually a definitive archival copy will be posted at www.aip.org/pt.