GNC1

GNC1 was the premier class in the 2015-16 AMA Grand National Championship for professional motorcycle flat track racing in the United States.

The GNC1 class debuted in the 2015 season, replacing the previous Expert division and combining both singles and twins events in a unified championship.

In GNC1, twin-cylinder motorcycles were the primary machines and were used for Mile and Half-Mile circuits while single-cylinder motorcycles were used for Short Track and TT events. Since 2017 the GNC1 class has been replaced by the new AFT Twins class, featuring twin-cylinder motorcycles at all events.

As of May 20, 2016

550-1250cc with the following restrictions: racing-only engines (Harley-Davidson XR750, Honda RS750, and Indian Motorcycle Race 750) may not exceed 750cc, engines greater than 1000cc are restricted to air/oil cooled.

300 pounds (136 kg) including fuel.

Dunlop DT3 19-inch flat track tires.

Sunoco Supreme 112

Dunlop DT3 19-inch flat track tires.

Sunoco Supreme 112

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