Pro Stock Motorcycle Pro Stock Motorcycle Pro Stock Motorcycle, formerly known as Pro Stock Bike, is a motorcycle drag racing class that is the two-wheeled equivalent of Pro Stock. It has been a feature of NHRA drag racing since the 1980s when it was added to the professional class structure and has since spread around the globe. The first points championship season was the 1987 NHRA season. The class has for years been dominated by inline-4 cylinder Suzuki based bikes but in recent years Harley-Davidson based V-twin machines have become more competitive due to favorable rule changes (160 c.i. Harleys vs. 107 c.i
Rokon (motorcycle manufacturer) problems with gear selection. Operation is loud (90.3 dB(A)) as the engine is always running fast except at idle. Despite low front wheel weight, about 43%, it had trouble pulling wheelies, a problem for Enduro riding. Prototypes were raced by factory riders from 1971 to 1973 under Tom Clark; "TCR" stands for "Tom Clark Replica". In the 48th annual six-days trial, The 4 riders earned 3 bronze medals and 1 silver medal. "Cycle Guide" test riders reported it superior for hill climbing and fast on hard surfaces, but poor on loose surfaces and descending hills. Rokon (motorcycle manufacturer) Rokon is