Not Long Ago NHRA Pro Stock Motorcycle Racing Was Living On Borrowed Time. Now, Thanks To The Introduction Of Harley-Davidson And Buell V-Twins To Challenge The Dominant Four-Cylinder Suzukis, We're Seeing The Fastest, Most Competitive Pro Stock Field In Years. But Is The Change All Good?
If you attended a National Hot Rod Association (NHRA) dragracing event a few years ago, you might have thought Pro Stock Motorcycles was a secret code for snack break judging from the way fans made a mass exodus to the refreshment stand every time the bikes took to the track. No one ever accused Pro Stock bikes of being boring: Pumping out 330 horsepower and rocketing from zero to almost 200 mph in under 7 seconds, these are some of the most explosive performance vehicles on the planet. In spite of this, Pro Stock bikes failed to attract the attention of the huge NHRA fan base in the same way as Top Fuel Dragsters and Funnycars. Years of rules neglect caused the class to stagnate to the point where nearly every round looked the same, with 16 cookie-cutter Suzukis all running ETs within a quarter-second of one another and the same handful of well-funded teams always coming out on top. Of course the crowd walked out.
Recognizing this problem, the NHRA took radical steps in 2002 to revitalize Pro Stock racing, rewriting the rulebook to make V-twin-powered racebikes legal to put more and different bikes on the grid. Some would suggest it even massaged the rules a bit to make the new bikes even more competitive to put an end to the Suzuki juggernaut. Harley-Davidson immediately stepped up with a V-Rod-based Pro Stock program (and now Buell is entering the class in '05), and the game was on. Finally the fans had something to cheer about-V-twins versus inline-fours, American bikes versus Japanese machines, new upstarts against established teams. And if you haven't attended an NHRA race lately, well, let us assure you the stands are no longer empty when the Pro Stock bikes run. Instead they are packed, and people are on their feet to see the V-Rods and Buells battle it out with the Suzukis (and the occasional Kawasaki). Diversity proves good for the sport.
Increased competition, of course, breeds increased controversy. Now that V-twin Pro Stock bikes have gone through their teething period and are proving competitive (some would say dominant: The Vance & Hines V-Rod won the '04 Pro Stock Championship, and Andrew Hines' V-Rod recently ran the first-ever 6-second Pro Stock pass), the paddock (and the internet) is awash with incendiary accusations. "The NHRA went too far; pretty soon it's going to be an all V-twin class," some are saying. "The Japanese bikes are getting pushed out because they're not American enough." With so many conspiracies flying around, discussions of NHRA Pro Stock programs almost sound like an argument between Kennedy assassination buffs.
The V-Rod and Buell teams have a solid program in place, and the pressure is on the four-cylinder teams to step up their game and find more power and speed to compete. But is there any merit to some of these conspiratorial utterings, and is there really a level playing field in Pro Stock? Have the new rules made four-cylinders obsolete? To get a handle on these questions we spent some time in the off-season with a leading four-cylinder team (Schumacher Racing/U.S. Army/Suzuki) and a leading V-twin effort (George Bryce's G-Squared Motorsports) to get an in-depth look at their programs and pose some of these questions to them. We also tried to do the same with the championship Vance & Hines V-Rod team, but we were denied access. Hmm, maybe there is a conspiracy at work.
After some firsthand observations at the preseason test-and-tunes we met up again with both teams at the opening round of the '05 NHRA season at the Gatornationals in Gainesville, Florida, to see how the V-twins stacked up against the "obsolete" fours in actual competition. The results were surprising. In spite of all the whining, Pro Stock, it appears, is not dead yet.
Schumacher Racing/U.S. Army SuzukiSince Suzukis ruled the Pro Stock paddock for so many years, it only makes sense to start our Pro Stock odyssey with one of the top Suzuki-based teams, the Schumacher Racing/U.S. Army effort that fields riders Antron Brown and Angelle Sampey. These are familiar names to any Pro Stock fan: Sampey is the winningest female racer in NHRA history and a three-time NHRA Pro Stock National champion; Brown finished third in last year's Pro Stock championship and has made 25 NHRA final-round appearances. With noted engine builder Steve Tartaglia (who has worked with both Star Racing and Vance & Hines in the past) serving as crew chief, Schumacher Racing clearly has the skills to make the Suzuki go fast.
We caught up with the Schumacher tractor-trailer at Bradenton Motorsports Park in Bradenton, Florida. Schumacher's bikes are a bit different from the other four-cylinder teams' because they are one of the few teams that build their own engines in-house; most Suzuki teams outsource engine work or lease their motors from an outfit such as Star Racing or Vance & Hines.
The basic platform for the Army bike is similar to what has ruled Pro Stock bikes since the mid-'80s, consisting of a Kosman rigid frame with a 70-inch wheelbase carrying a 92-cubic-inch (1507cc) Suzuki inline-four-cylinder motor pushing a minimum of 600 pounds total weight (including the rider), all in accordance with NHRA rules. The engine is built around vintage Suzuki GS1150 cases (actual Suzuki pieces, not aftermarket copies) and uses a surprising number of stock Suzuki internals, including a clutch hub, plates and springs and stock shift forks and shift shafts. The crankshaft is an aftermarket piece from Falicon, the cylinders and pistons are from MTC and the cylinder head is from Vortex. Schumacher opts for an aftermarket two-valve head since NHRA rules allow a displacement advantage for two-valve bikes compared to four-valvers, which are limited to just 1429cc. "There's no replacement for ccs," Brown tells us.
NHRA rules demand that all four-cylinder bikes use carburetors, not fuel injection (which is legal for V-twins), but the carbs on the Army bikes are nothing like those on your street Suzuki. "On a streetbike carb you have the main jet on the bottom," Brown explains. "We make the jet changes up on top. The carburetor can't supply enough fuel to the motor when it's breathing, so it sucks it from the bowl direct to the top power jet. At the top of each gear our bike runs fat, unlike the V-twins that have fuel injection so they can control the whole fuel curve. That is definitely an advantage for them."
That, in a nutshell, is a cutting-edge inline-four Pro Stock machine, if you consider engine cases from the '80s and bodywork based on the '98 GSX-R1100 cutting edge. Brown says Suzuki would love to see more modern, Hayabusa-based Pro Stockers on the grid (and in front of potential bike buyers in the stands), but the rules won't allow it. "That is what is really holding the Suzuki guys back from progressing," Brown said. Still, with Tartaglia at the wrenches the Army bike presents a potent package, producing approximately 330 hp at 13,700 rpm.
G-Squared Motorsports Buell
It's a surprise to many to see Bryce spinning wrenches on a V-twin-powered Buell racebike this year-after all, Bryce has been riding and tuning Suzukis and Kawasakis for the past 26 years (winning six NHRA championships in the process), so working on a V-twin is a huge departure for him. Bryce tells us he's been collaborating with S&S;'s George Smith (the other G in G-Squared Motorsports) on this V-twin Pro Stock project since '99, though, so this isn't something he dreamed up overnight.
We met with the G-Squared outfit at South Georgia Motorsports Park in Valdosta, Georgia, where we got an exclusive first look at the all-new G-Squared Motorsports Buell that will be ridden this year by multitime AMA/Prostar champion dragracer Chip Ellis. Aside from the same 70-inch wheelbase, there are virtually no similarities between the Buell Pro Stocker and the Suzuki. For starters, the V-twin motor is a monster compared to the Suzuki, displacing a full 160 cubic inches (or 2622cc, the NHRA's displacement limit for 60-degree, pushrod V-twin motors). This 68-cubic-inch advantage is intended to make up for the limited rpm potential of a two-cylinder motor. Bryce explains, "We used to say, 'There's no replacement for displacement,' but it turns out there is-and that replacement is rpm. A motorcycle engine is basically an air pump, and the more air you can pump, the more power you can make. There are two ways to do this: Make a bigger pump or spin the pump faster. A 160-cube V-twin that redlines at 8500 rpm will have to pump a lot of air to make as much power as a 92-cube four-cylinder that turns 13,700 rpm."
The motor itself is built entirely by S&S;, featuring a one-piece billet block, integrated transmission housing and coffee-can-sized, five-inch-diameter pistons with 1.5-inch crankpins (the sheer mass of these parts explains why rpm is limited to just 8500 revs). Another key difference with the V-twin bike is that NHRA rules allow modern fuel injection instead of old-school carburetion, allowing the V-twin tuners to precisely control fuel delivery over the entire rev range via a laptop using S&S-developed; tuning software.
The G-Squared Buell makes around 335 hp at 8500 rpm-more or less right in the neighborhood of the quickest Suzukis-and it has to push a few more pounds (615 is the class weight minimum for V-twins). In theory, all these variations in displacement, minimum weight, carburetion versus injection and body configuration will have an equalizing effect between V-twins and inline-fours, making two very dissimilar machines go down the quarter-mile at roughly the same rate-which should make for close, competitive racing, right?
Vance & Hines/Screamin' Eagle Harley-Davidson V-Rod
The S&S-powered; Buells are not the only V-twins in NHRA Pro Stock, and they're not the first-that designation goes to the '04 championship-winning Vance & Hines Harley-Davidson V-Rod. Debuted in '02, the V&H; effort has a three-season head start on the S&S; program. Built to the same rules as the Buells (160-inch displacement cap, 615-pound minimum weight), there are some obvious similarities between the bikes, which both use 60-degree, fuel-injected V-twin motors. The V-Rod's engine was primarily designed by dragracing legend Byron Hines with some assistance from Harley-Davidson engineers, race team manager Anne Paluso tells us. The only part not built by the H-D/V&H; team is the fuel injection system, which comes from MoTec. We apologize for being so thin with specific details on the V-Rod's configuration, but Harley-Davidson guards the details of its Pro Stock program with a ferocity matched only by the Pentagon and its handling of sensitive nuclear secrets. Unlike Schumacher and G-Squared, both of which offered us unlimited access to their programs, Harley-Davidson forbid us from attending any tests, speaking to any team members or even photographing their bikes for this article. The team is so secretive about the exact configuration of their motor they even go so far as to drape towels over it when they're working in the paddock.
One key difference between the S&S; Buell motor and the V-Rod powerplant is cam position and pushrod length. On the Buell the cams are located at the bottom of the Vee, like a production Buell's (or Harley-Davidson's) motor, and the overhead valves are actuated by standard-length pushrods. On the V-Rod the cams appear to be located higher on the motor (where the cam pulleys are visible in pictures), which allows the team to use shorter internal pushrods that, in theory, reduce reciprocating mass and allow higher ultimate rpm. Indeed, the Harley-Davidson motor is said to reliably produce 330 hp at 9500 rpm-about 1000 rpm higher than the Buell motor.
Herein lies the controversy: NHRA Pro Stock rules specifically state that the engine must be designed and manufactured for a production motorcycle. This isn't an issue for the Suzukis-the Schumacher bikes (and most others) use factory Suzuki cases. Although the factory Harley-Davidson V-Rod does use a 60-degree V-twin motor, it's equipped with overhead cams (no pushrods); furthermore, not even H-D's pushrod motors have cams in the same place as the Vance & Hines Pro Stock motor, calling into question its conformity to the "production" rule. Note that the S&S; Buell motor isn't immune to this criticism either: Its cams are in the right place and the pushrods are the right length, but production pushrod Harleys and Buells have a 45-degree cylinder angle, not 60 degrees like the Pro Stock bikes.
One other difference-if you want a Buell Pro Stock bike of your own, all you have to do is dial up S&S; and they'll gladly sell you either a motor or a complete bike. Same with a Suzuki-ironically, if you want to buy a championship-caliber Suzuki, Hines is probably the guy to call. The Harley-Davidson V-Rod, on the other hand, is pure unobtanium and at this time only available to the factory team. Paluso assures us this won't be the case for long, though. "Our plans are to expand the program, but it won't be just selling the engine, it will be a whole racebike. But we want to get this bike successful first. Our intention is to have more V-twins on the track."
Adding It All Up
When the NHRA circus arrived in Gainesville, Florida, for the season-opening Gatornationals '05, all the off-season controversy had created an especially high level of interest in the class. This was hyped up even further when fans were reminded of race tire manufacturer Mickey Thompson's Six Second Pro Stock Club, created in '02, that promised a $10,000 prize for the first Pro Stock rider to record a 6-second pass at an NHRA national event. There was a record-breaking crowd at Gainesville this year, and you can bet many of them were expecting to see a 6-second pass.
Conditions were ripe for records at G-ville, with unusually cool temperatures producing just the type of dense air that helps these mountain motors make good power. Sure enough, in the first round of qualifying U.S. Army rider Sampey set a new track record of 7.029 seconds at 187.89 mph on her Suzuki, followed by Geno Scali's Suzuki in second position and Sampey's teammate Brown in third. Who said inlines are obsolete?
For the second round of qualifying the air temp dropped to 57 degrees F, even better for a record run. Suzuki rider Michael Phillips got the first try and fell way short. Next up was Ryan Schnitz on the Muzzy/S&S; Buell, who blew through the traps at 7.057-close but no cigar. At the end of the session Vance & Hines rider GT Tonglet lined up his V-Rod against Craig Treble's Suzuki and flashed 7.001 at 197.45 mph on the scoreboard-oh so close (and a new track mph record)! But in the end the honors fell to his teammate, defending class champion Andrew Hines, who made what was probably the greatest pass in Pro Stock history, turning in a 6.99-second performance. Bust out the checkbook and make it payable to Hines, who finally made it happen on a V-twin V-Rod.
Race day saw the fastest field in NHRA Pro Stock history, with all 16 bikes coming in under 7.149 seconds. And all configurations were represented: two V-Rods, two Buells, 11 Suzukis and one lone Kawasaki, Scott Valetti's Lake Mortgage-sponsored Ninja, in the 13th spot with a 7.136 ET.
Round One had some riders seeing red, specifically Chip Ellis on the G-Squared Buell and Valetti on the Kawasaki, who both drew red lights. Schnitz's Muzzy Buell just didn't have the speed it did in qualifying, and it was more bad news for the V-twin camp in Round Two when Hines fouled out with a red light and Tonglet's V-Rod suffered mechanical ills. With all the V-twins out of the picture it was a guaranteed Suzuki final. First Brown faced off with teammate Sampey and took the win when Sampey red-lighted. Steve Johnson was Brown's next opponent, and Johnson got off the line first and took out the last U.S. Army bike. Johnson continued his streak right up to the final round, where he overcame Treble on the plum (not purple!) Matco Tools Suzuki to take his second career victory-using a Vance & Hines-built four-cylinder motor! Vance & Hines got the 6-second glory, but when the points were on the table they were beat at their own game by one of their own bikes. Oh, the irony.
So, are V-twins the end of NHRA Pro Stock as we know it? From what we saw at Gainesville, it ain't dead yet!