NHRA Adjusts Pro Stock Motorcycle Weights

It sure looks like Vance & Hines, together with Monster Heads did too good a job with their new Suzuki four-valve engines encased in Hayabusa bodies. NHRA is clamping down on the Pro Stock Motorcycle class – again – because tenacious developers and builders are doing such a good job as to make the two-valve Suzuki engines and S and S Buell/EBR engines irrelevant during the 2023 NHRA Camping World Drag Racing Series.

There have only been two races in this class held to date. Pro Stock Motorcycle’s third race of the year takes place in two weeks at Route 66 Raceway in Joliet, IL. a suburb of Chicago. Gaige Herrera, who joined Vance & Hines this year after a half-season that started at last year’s U.S. Nationals, has won at both the season starter in Gainesville and at last week’s 4Wide contest in Charlotte.

Still, NHRA wants to see more parity in the class and has made weight changes to both the Buell and Suzuki engines – both the latter’s two- and four-valve entities.

Marc Ingwersen and Ryan Oehler both ride Buell motorcycles – Anne Proffit photo

The changes begin with NHRA-accepted S and S engines. There are two iterations of these engines, a Gen 1 and Gen 2. Their sizes range to a maximum of 160 cid; both have a 60-degree angle, are two-valve pushrod mills and, henceforth, both of them will hit the water box weighing an unchanged 635 pounds.

Steve Johnson has found success with Monster Heads’ four-valve engines – Anne Proffit photo

On the Suzuki side, again with all engines meeting NHRA stipulations, the maximum 113cid 2-valve Suzuki lost 20 pounds and has gone from a minimum weight of 590 pounds to 570 pounds. On the four-valve side, there are different weight penalties for the Vance & Hines vs Monster heads. The V&H four-valve engine must weigh a minimum of 635 pounds, a net gain of 10 pounds, while the Monster head-employed Suzuki four-valve gains only five pounds, from 625 to 630 pounds.

Chase Van Sant’s WAR Racing Suzuki four-valve motorcycle uses Vance &Hines heads. Photo: Anne Proffit

These changes were made, NHRA said, strictly to control performance and maintain parity in the category. The question is whether the superb tuners whose job it is to make sure their motorcycle beats anyone else’s will find a way to offset these changes at the upcoming race in Joliet, or whether they’ll have issues on their hands.

One thing NHRA didn’t address in this class is runaway bikes, like Marcus Hylton’s Round 1 trip to the Charlotte sandbox on his Buell motorcycle. And no, putting chutes on these motorcycles isn’t the best idea. Nearly every rider and team uses the best brakes available so they don’t end up in the sandbox and Hylton’s issues in Charlotte shouldn’t be the impetus for yet another rules change.

About Anne Proffit 1269 Articles
Anne Proffit traces her love of racing - in particular drag racing - to her childhood days in Philadelphia, where Atco Dragway, Englishtown and Maple Grove Raceway were destinations just made for her. As a diversion, she was the first editor of IMSA’s Arrow newsletter, and now writes about and photographs sports cars, Indy cars, Formula 1, MotoGP, NASCAR, Formula Drift, Red Bull Global Rallycross - in addition to her first love of NHRA drag racing. A specialty is a particular admiration for the people that build and tune drag racing engines.

1 Comment on NHRA Adjusts Pro Stock Motorcycle Weights

  1. They did the same thing to Harley. Don’t know if that’s why they left but it would upset me.They try to do their best then nhra says no you can’t do your best.

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