About the AMA Pro Grand National Expert Twins Championship
The Motorcycles of AMA Pro Flat Track - Twins
Grand National Championship Experts (Mile and Half-mile)
- Top Speed: Over 130 mph
- Engine Displacement: 550cc - 1250cc with the following restrictions, racing only engines may not exceed 750cc, engines greater than 1000cc are restricted to air/oil cooled.
- Eligible Bikes: Aprilia RSV 1000/550, BMW FS 800, Buell CR1125/XBR/1200, Ducati 748/848, Harley-Davidson XR 750/XR1200/883, Honda RS 750, Kawasaki 650 Ninja, KTM 990 Super Duke, Suzuki TL 1000/SV 650/680/750, Triumph Bonneville Scrambler/America/Speedmaster, Yamaha Tenure 750
- Minimum Weight: 310 lbs with fuel.
- Fuel: Sunoco Supreme 112
- Front Tire: Dunlop/Goodyear DT-11 27.0x7.0-19 D3616/CD-5
- Rear Tire: Half Mile and Mile: Dunlop/Goodyear DT-11 27.5x7.5-19 D1637/CD-8
- Short Track and TT: Dunlop/ Goodyear DT11 27.5x7.5-19 D1657/CD-5
AMA Pro Grand National Expert Twins are the most powerful machines on the circuit. Reaching speeds in excess of 130mph, the large-displacement motorcycles are based on a rule set that allows for a variety of performance modifications.
All machines run on purpose-built Goodyear tires and are fueled by Sunoco Supreme 112 race fuel.
As impressive as the machines are in the Twins Engine class, it is the all-star lineup of riders that truly put on the show. Bryan Smith will be looking to defend his title in 2013 on the back of his Kawasaki. Smith dominated on mile-long tracks and got the most out of his machine on the lengthy front and back stretches each course had to offer. However, like in 2012, Smith will be flanked by the likes of Sammy Halbert, Jake Johnson, Jared Mees and others as each competitor will be hungry for a shot at the Grand National Championship Expert Twins class in 2013.