In the United States, more people buy mountain bikes than any other type of two-wheeled, pedal-powered transportation yes, even with the surge in road-bike sales after Lance What's-His-Name won all those races. That means you probably have a mountain bike, but you tend to ride it on the sidewalk, when you should be cranking through trails. Lucky for you, the Gateway Off-Road Cyclists Midwest Mountain Bike Festival is this Friday through Sunday (April 7 to 9) in Klondike Park (4600 Highway 94 South, Augusta). The festival is expected to draw cyclists from fourteen states, so dust off your old Diamondback (or whatever) and go; it's $20 to register in advance and $25 the weekend of the event. This just might prove to be more mountain-bike madness than you can handle, so take it easy with bicycle-advocacy discussions Friday night; a festival with food (a pig roast!), drink (New Belgium beer) and bands on Saturday; and a 43-mile ride on Sunday, with shorter rides sprinkled throughout the weekend. Visit www.gorctrails.com for maps, schedules and other information, or call 636-949-7535.