/cloudfront-us-east-1.images.arcpublishing.com/octane/4VRABCC6X5FHJCWL2J6AAQFMOM.jpg "Vance & Hines Gen III Hayabusa Pro Stock Motorcycle")
The tree goes inexperienced and energy is unleashed. Clutches chunk and engine torque turns 10-inch-wide slicks. The bikes hunker as tire sidewalls are twisted into wrinkles. Roughly 2,000 kilos of drive on the tire footprint launches every bike. It is a lovely second of balanced forces—entrance wheels carry and wheelie bars might contact frivolously, however so completely does this all occur that nothing upsets the drive being generated between rubber and pavement. The bikes cowl the all-important first 60 toes in only over one second. You possibly can’t fall 60 toes that quick on this planet.
Later I checked out tires—they’re neither shredded nor melted. I noticed a velvety uniformity on their surfaces, with solely delicate diagonal traces of the graining seen in different bike pavement sports activities.
Drag Racing Outgrows Manufacturing Components
NHRA’s Pro Stock Motorcycle (PSM) drag racing class started within the Seventies, based mostly on modified manufacturing bikes. That made it engaging to each spectators and to starting builders. These have been the heady days of horsepower revolution—two-stroke 750 Kawasaki H2s and four-stroke 903 Z1s raced in opposition to the brand new GS Suzuki fours and “constructed” Harleys.
Within the gentle of day at NHRA nationals, spectator consideration was rigorously targeted on Professional Inventory Bike by sustaining primary visible connection to manufacturing fashions we’d personal and journey—however radically modified in keeping with the standard American perception that an excessive amount of is simply sufficient.
Within the last days of World Struggle II, aviation was the primary US trade in greenback quantity, working three shifts of expert machinists, welders, fabricators. In August 1945 all of it stopped, and in two years it fell to seventeenth. A flood of surplus know-how poured onto the market at pennies on the greenback. Need a Lockheed P-38 Lightning? Yours for $1,200. One fast-mover bid on 1000’s of surplus platinum-gapped plane spark plugs and put high-school children to work with diagonal slicing pliers, nipping off the bits of treasured steel.
Artwork grew from these abilities and that surplus—hot-rodding! Customized-built automobiles and bikes grew to become a dynamic tradition. Sanctioned drag racing took the place of midnight contests.
Professional Inventory Bike Outgrew Its Roots
Efficiency in NHRA Professional Inventory Bike rose so excessive that it has outgrown the Seventies manufacturing {hardware} from which it grew. Usable GS Suzuki crankcases at the moment are uncommon. Just like the Prime Gasoline automobiles whose engines are “Chrysler-inspired” however 100% Mopar-free, so the engines of right this moment’s PSM retain solely conceptual similarity to the unique manufacturing powerplants.
That is what occurs when many ingenious minds and hard-driving personalities commit themselves to going faster and sooner over a long time. On the latest Charlotte, North Carolina, NHRA nationwide I spoke with Eddie Krawiec, an lively PSM rider, and with Andrew Hines, a driving drive in Vance & Hines’ newest PSM creation. Hines mentioned inventory crankcases for the Seventies–80s Suzuki GS-series are gone, so groups working Suzukis turned to 1100 and 1150 instances. However crankshafts spinning at 14,000 rpm need out so badly that 40-year-old instances could also be good for under 5 runs!
Why? As a result of this 12 months’s Gen III Vance & Hines “Hayabusa” PSM is making 400 hp at 13,800 rpm—5 occasions the ability of the unique engines. That requires sturdy assist to stop longitudinal whip. Classic castings can’t give it.
The Origin of Billet Engines in PSM
At first of this century NHRA had a brainstorm: Do one thing for the massive numbers of Harley-Davidson riders and admirers who have been discovering much less and fewer encouragement on the drag races. Simply as has occurred to inventory Suzuki components on the 400 hp degree, Harleys constructed from a mixture of inventory, modified, and aftermarket components weren’t as much as the job of competing with extra trendy designs, equally modified.
Why not construct a very new engine sharing identifiable options of Harley-Davidson V-twins, however designed for drag racing with sufficient displacement to make them win races? Construct it, name it a Harley, and see if individuals imagine it! Harley-Davidson and Vance & Hines made it occur in 2002: a 60-degree V-twin with two big valves per cylinder, operated by pushrods and rockers. They gave it 160ci, and to reliably comprise the ability, its total construction was CNC-milled from stable billet. Previous-time hot-rodders operated lathes and milling machines by hand, however this was Byron Hines studying the mysteries of CNC through Solidworks and CATIA—the best way aerospace does issues.
It labored. It has labored for years, so nicely that when aftermarket producer S&S needed in on the act, its mighty V-twin was assigned the name “Buell.” Harley followers now had stable winners for which to cheer themselves hoarse. Their sworn enemies, “rice-burners” and “crotch rockets,” have been reduce all the way down to measurement.
Suzuki builders responded with higher-lift cams—till the taller lobes threatened to overhang the perimeters of their tappets. They bored tappet guides larger, for larger tappets. When that ran out of steel, they switched to “radius tappets” (humped-up within the center to extend carry, and keyed to stop rotation). After which V&H and others started to CNC-machine completely new Suzuki heads from billet—a brand new software within the cam-lift race.
At Final—A Billet “Suzuki” to Equal the Billet Harleys
Once in a while through the years NHRA have seen match to regulate PSM guidelines, over time nudging Suzuki displacement to the current 107 and 113 (with differing weights). The newest change has been to approve an entire “billet Suzuki” with 4 valves per cylinder (as in all present-day manufacturing Suzukis). Though the billet engine shares quite a few options with the unique GS engines of 1976-onward (their central cam drive and curler crankshaft) its official identify needs to be “Gen III Hayabusa” as a result of that’s Suzuki’s present new mannequin delivering highest straight-line efficiency.
Why the V-twins Get 160 Inches
Individuals wish to know why the V-twins get 160 cubes when the fours get solely 107 or 113. The reply is easy. The fours, whose strokes are quick, can attain revs roughly 40 % increased than can the monster twins. If we multiply 113 cubes occasions 1.4, we get 158.2. This tells us that NHRA-approved PSM twins and fours can pump the identical quantity of fuel-air combination per minute (cylinder displacement multiplied occasions rpm), giving them equal potential for making energy. The remaining is as much as the builders, tuners, and riders—with NHRA tweaking the principles as wanted to maintain the ticket demographics candy.
The essential remainder of the PSM guidelines is that wheelbase is 70 inches most, rear tire width is 10 inches, and the gasoline is an authorized gasoline.
What Brings Suzuki and Vance & Hines Collectively?
After a protracted partnership with V&H in PSM and American Flat Track, Harley-Davidson not too long ago ended that relationship. Suzuki noticed Professional Inventory Bike as the best venue wherein to current its new Gen III Hayabusa manufacturing bike. Hayabusa lives in its personal particular class as a result of it embodies final avenue acceleration. It drives one of many largest aftermarkets in motorcycling as a result of its consumers additional customise and intensify it for their very own functions. It is rather a lot in Suzuki’s curiosity to protect and domesticate that “particular relationship.”
The Little Man Versus the Huge Outfits
Individuals have at all times rooted for the underdog, however drag racing at its highest ranges can not be based mostly on DIY hot-rodded manufacturing bikes within the outdated method. In the event you or I resolve to provide PSM a attempt, we’ll discover ourselves competing in opposition to the very individuals who provide the components we have to be aggressive—outfits like Vance & Hines.
In studying for background data, I found a beautiful sentence written by somebody calling himself “McGuire”:
“The historical past of Prime Gasoline and Humorous Automotive appears to be that anybody that strays from the herd with a brand new thought goes bankrupt earlier than they get the thought developed or discover the appropriate mixture…or they do get it proper and the rule e-book is modified to outlaw their innovation.
Does this imply the little man will at all times lag behind the outfits like V&H who produce the components everybody must be aggressive, and which NHRA must preserve its lessons wholesome? Huge outfits have huge benefits, however lengthy expertise with what you’ve gotten may also win races. When the large guys innovate, they create contemporary unknowns for themselves. We noticed this in MotoGP final 12 months, when the 2022 Ducatis have been a thriller, whereas riders and groups with one- or two-year-old bikes had confirmed setups and will get outcomes from the primary race. An instance from PSM is veteran competitor Steve Johnson, who stays surprisingly quick due to his expertise with what he has, regardless of not having the most recent excessive stuff.
Subsequent, we’ll have a look at the main points of what V&H has delivered to NHRA Professional Inventory Bike.