On Thursday, the U.S. track cycling team will compete in a London velodrome, riding fixed gear bicycles that have pedals chained directly to the rear wheel--so that whenever the wheel spins, so do the pedals. The Olympians will reach speeds of over 50 miles per hour and ultimately have to stop their bicycles using their leg strength, because track bikes don't come with brakes. Taking a cue from these velodrome racers and city bike messengers, a growing number of teenagers are jumping on fixed gear bikes on urban streets, too. Fix gear bikes are not new; it's early 19th century technology. But cyclists who ride them today swear by them, as do the young Latinos who have built a culture around "fixies" in cities around the country. The growing popularity may be because fixed gear bikes are (or were?) affordable. As [Wired](http://www.wired.com/gadgetlab/2009/06/specialized-to-roll-out-cheap-fix...) put it: "Find an old beat-up road bike, buy a new hub and throw away all extraneous hardware. You now have a fixie." But the young Latino fixie riders I spoke to said it was a lot more than that. They cited everything from design of the bikes to the sense of community they get when they join riding groups. Others also expressed hopes of riding professionally. Watch the video above and listen to young riders in Los Angeles describe for themselves why they prefer fixed gear bikes.