Bicycle motocross or BMX is the sport of racing bicycles in motocross style on tracks which use an inline start and have obstacles, and also refers to the bicycle itself, which is designed for dirt and motocross cycling. BMX began in the early 1970s when children began racing their bicycles on dirt tracks in southern California, inspired by the motocross stars of the time. The size and availability of the Schwinn Sting-Ray and other wheelie bikes made them the natural bike of choice for these races, since they were easily customized for better handling and performance. BMX racing was a phenomenon by the mid-1970s. Children were racing standard road bikes off-road, around purpose-built tracks in California. The 1972 motorcycle racing documentary On Any Sunday is generally credited with inspiring the movement nationally in the United States; its opening scene shows kids riding their Sting-Rays off-road.
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