Following a review of recent performances in the Pro Stock Motorcycle category, NHRA has announced that the minimum weight for the Harley-Davidson 160-cid, four-valve combination will increase 20 pounds, from 640 to 660.
The adjustment is part of NHRA’s ongoing efforts at maintaining competition and parity within the category. The change becomes effective April 27, 2012, at the O’Reilly Auto Parts NHRA Spring Nationals presented by Super Start Batteries in Houston, which is the next stop in the NHRA Full Throttle Drag Racing Series for Pro Stock Motorcycles. The minimum weight for NHRA-accepted American pushrod V-Twin 160-cid will remain at 615 pounds, and the Suzuki 107-cid two-valve will remain at 595 pounds.
NHRA will continue to monitor performance and will make adjustments as necessary.
20 pounds?…that’s not enough…
If the Harley can run the 4 Valve 160 cid at 660 lbs.The Buell 160 cid at 615 lbs. The Suzuki 107 cid two valve at 595 lbs.Can I build a Kawasaki Z1 two valve motor and if so what size motor,and weight