Though their business now includes engine part sales to hot rodders, including the supply of the remarkable boss nine engine. For 20, harleydavidson and buell will both be allowed a maximum 160cubic inch displacement cid, for a 60degree, twovalve, pushrod engine. Motorcycle drag racing veteran and seventime nhra winner chip ellis will make his return to the nhra pro stock motorcycle. In a historymaking decision made at the request of the teams, nhra will allow pro stock racers to run any currently approved engine combination in any currently approved body, regardless of the. The history of the pro stock class is being celebrated by nhra in 2020 with a 50 years of pro stock salute. Pro stock motorcycle, formerly known as pro stock bike, is a motorcycle drag racing class that is the twowheeled equivalent of pro stock. But since the rule change on the friday following the chevrolet performance nhra. Nhra pro stock motorcycle bryce wants a vance and hines vrod jack korpela. Competitors rely on spec racing gasoline to produce elapsed. Early 500inch pro stock engines using the old bow tie block had a bore around 4.
Below lie the complete set of rules for pro stock eliminator in the year 1974. New billet 4valve cylinder head approved for suzuki nhra pro. Must be stocktype engine specifically designed and manufactured for. Mountain motor information jon kaase racing engines. New billet 4valve cylinder head approved for suzuki nhra. Nhra mello yello drag racing series 5th paragraph page ix 1092019 pro stock motorcycle is the twowheel category in the nhra mello yello drag racing series.
Nhra top fuel engine specifications by phil whitmer. The lightweight drag rails can travel a quartermile in 4. Reserved for 1955 or newer modelyear factory production automobiles and some sports cars. I bought the cheapest bike at the motorcycle auction duration. Nhra to allow any accepted enginebody combination in pro stock. One of the key parts of these rules is the factoring numbers that are near the top of the rules. The current nhra pro stock motorcycle elapsed time record is 6. Since 2016, pro stock teams have used holley efi as mandated by nhra rules. Jr street rules section of nhra rulebook hot rod heritage racing.
The rules that exclude forced induction of any sort, plus allowing head modifications, have resulted in pro stock heads being the most sophisticated in any drag racing category, with valve lifts in the 1 region. Pro stock motorcycles drag racing nhra 200mph race. Bryce had been a mainstay in nhra pro stock motorcycle since the beginning. Inside a pro stock motorcycle engine nhra nhra national hot rod association. Nhra is taking the rivalry to another level in 2018 with its pro stock category by allowing any approved engine to be installed in any nhra legal body.
You see, george bryce of star racing came up with the idea to bring a bonified vtwin into the nhra pro stock motorcycle ring. Current regulations also require a throttle body with a maximum opening of 25square inches and a spec ecu engine. This cylinder head is eligible for pro stock motorcycle use only and is contingent that all units must continue to meet all applicable requirements of the nhra rule book. Before this rule change, all three makes had the same minimum weight. The engine is built around vintage suzuki gs1150 cases actual.
Motorcycle drag racing also known as sprints involves two participants lining up at a. The first points championship season was the 1987 nhra. The nhra is extreme no matter how you look at it and when you crash at speeds of nearly 400 miles per hour it can be very ugly but at the same time you cant look away. Deflorians mountain motor pro stock engine measures in at 825 cubic inches more than double the size of say, a dodge demon. Is the new nhra pro stock motorcycle rule a kneejerk reaction. Classbyclass regulations and requirements, racing procedures, and. Pro stock motorcycle is the twowheel category in the nhra. Pro stock engines use electronic fuel injection and spec gasoline and are restricted to a maximum of 500 cubic inches. The 2020 nhra rulebook is now online and viewable by all who wish to compete in the nhra arena.
Then that winter, they threw the rule book off the top floor of the nhra. 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. Racers wanting a pro tree must have a p before their dialin. Building a vtwin prostock engine by derek churchwell. This cylinder head is eligible for pro stock motorcycle use only and is contingent that. What goes into rebuilding an 11,000hp top fuel dragster engine.
The late dave schultz is the alltime leader in pro stock. As the structure of the blocks became stouter, engine builders consistently enlarged the bore as far as they dared so that bigger valves could be stuffed into the cylinder head. National hot rod association masthead remove all of page iii page iii 1092019 introduction. Nhra to allow any accepted enginebody combination in pro. Refer to the current nhra rulebook or nhra rule amendments for. After the season opener at the 50th amalie motor oil gatornationals in gainesville, florida. Matt smith makes the fastest pro stock motorcycle run in. Nhra changes pro stock engine rules racepages digital. Senior editor kevin mckenna takes you inside a pro stock motorcycle engine with this technical breakdown. It was this factoring by nhra that would lead directly to the development of the vehicle known as the taxi.
Power rankings are a rating used to rank race teams against each other and are updated on a. Changes to the design, functionality or configuration of the. Nhra announced changes to the pro stock motorcycle category. Is the new pro stock motorcycle rule a kneejerk reaction. The bestknown form of motorcycle drag racing is the pro stock bike category, although several other categories exist, including 1,000 horsepower 750 kw nitromethane engine. Not long ago nhra pro stock motorcycle racing was living on borrowed time. At the center of this latest commotion is the nhra tech committees rule changes following. Is the new nhra pro stock motorcycle rule a kneejerk. Nhra adjusts pro stock bike engine rules speed sport. The cars have come a long way since their debut at the 1970 winternationals. While the suzuki engine is an unsupported antique in this.