From Wikipedia, the free encyclopedia This article is about bicycle events. For the nuclear reaction, see Critical mass (http://en.wikipedia.org/wiki/Critical_mass). For other uses of the term "critical mass", see Critical mass (disambiguation) (http://en.wikipedia.org/wiki/Critical_mass_(disambiguation)). San Francisco (http://en.wikipedia.org/wiki/San_Francisco) Critical Mass, April 29, 2005.
Critical Mass is a bicycling (http://en.wikipedia.org/wiki/Bicycle) event typically held on the last Friday of every month in over 300 cities around the world.
The routes for The Cleveland Critical Mass change monthly. They often get food afterward. Looks like a great time. They usually ride for about an hour rain or shine.