just goofing off and seen this about a guy going 108.92 mph on a bike im not sure of myself yet at 15 and up ( only hit those going down hill)
http://www.bicyclemuseum.com/Html/bike8.html
scroll down to the 1941 Schwinn Letourner Replica thats where it talks about it. and thats one heck of a crank on that bike also