Bicycle motocross (BMX), which was included among Olympic events in 2008, was originated in California in the 1970s. At that time, in BMX races, SHIMANO DX was used by the Shimano Factory Team, which included Bobby Encinas, a BMX racer who won more than 400 races in the United States. It was a practical components series for top professional racers that Shimano launched at a time when no dedicated BMX parts existed. To meet the demands of BMX races, which were so fierce as to be called “fighting sport using bicycles,” from dirt corners to jumps, SHIMANO DX achieved high stiffness of the front chainwheel, cassette sprockets and other components. The explosion of BMX’s popularity in the United States led to the subsequent mountain bike boom in the 1980s, later bringing many prominent racers into the world beyond the boundaries of the sport. In 1996, Shimano introduced SPD pedals equipped with functions suited for BMX onto the market.