The AMA Motocross Championship is an American motorcycle racing series. The motocross race series was founded and sanctioned by the American Motorcyclist Association in 1972. The series is the major outdoor motocross series in the United States and is sanctioned by AMA Pro Racing and managed by MX Sports Pro …

One of the most traditional forms of motorcycle competition in the United States, flat track racing grew from the age when riders would compete on county fair horse tracks groomed to deliver a hard-packed surface. Since 1975, the AMA Flat Track Grand Championship has pitted top amateur flat trackers against …