AMA Grand National Championship flat track motorcycle racing series is the official event approved by the American Motorcyclist Association. Nowadays, there are actually a range of races, but this originally began as one event, known as the Class A Dirt Track Championship.

However, during the Great Depression, it became far too expensive to manufacture Class A vehicles, and racing Class C machines gradually became more popular. However, until 1953, the championship was still based upon the drivers performance in a single race, which was known as the Springfield Mile. In 1954, the championship expanded, and began to feature five different races - four of which were helt on dirt tracks, with the final race taking place on an asphalt paved course.

During this period, notable motorcycle manufacturers also came to be associated with the sport. In the same way that, more recently, websites such as Partypoker.com have come to be associated with online casino gaming, certain brands quickly became renowned for producing motorcycles which were specifically designed for racing. Harley Davidson had already gained prominence within the AMA events, but names such as Yamaha and Triumph achieved a certain notoriety during this time.

By 1983, the AMA Grand National Championship was officially the best attended form of dirt track racing in the US. At this time, motorcycle engine technology had improved, but it was often too powerful for the bike frames and tires. This mean that road racers often took on a 'spin' style of racing, which was closer to what we would today associated with dirt track performances.

However, dirt track racing was actually declining in popularity, due to the fact that the bikes which were used for this type of racing could not be bought directly from manufacturers. Road racing events became part of a completely separate series, both of which continue to take place today.