Bike racing is dangerous enough without "official" obstacles. 

Irish cyclist Matt Brammeier had a horrific crash while he tried to rejoin the peloton during the Tour of Utah. Obviously, Brammeier was coming down the hill at Guardsman’s Pass in Big Cottonwood Canyon far too fast to make the turn, and went straight into a team car at a speed I don’t even want to guess. » 8/10/15 11:59am 8/10/15 11:59am

A backwards bike = major brain fuckage. 

Engineer Destin Sandlin runs a video channel called Smarter Every Day. This video of his (found on Kottke.org) shows just what can happen when you challenge your brain. When he tries to ride a bicycle that’s been altered to steer backwards... chaos ensues. Eight months later, he’s taught himself to ride the “backwards… » 4/28/15 2:49pm 4/28/15 2:49pm