Motocross is a form of motorcycle or all-terrain vehicle racing held on enclosed off-road circuits. It is often shortened to MX or MotoX. Racers start simultaneously and the first rider across the finish line wins. Events typically include up to 40 racers.

TIMING:Top level racing can last more than 30 minutes, while amateur races can be as short as 10 minutes. As the time period ends, a finish line flagger signals racers that there are just one or two laps left. The race finishes with a checkered flag.

TRACK: Motocross tracks can be around 1 to 2 miles long. They incorporate natural terrain features with varying amounts of man made jumps. Some tracks are made entirely of hills and turns with no jumps.

MAJOR COMPETITIONS: The Grand Prixs — World Championship Series, held traditionally in Europe, and the American Motorcyclist Association American National Championship, held in the United States.

AMERICAN RIDERS: Randy Carmichael, John Dowd, Mike LaRocco, James Stewart Jr., Ryan Villopoto, Kevin Windham.