Based off 450 motocrossers, the new Roland Sands designed 450 SuperSingles may be running at a racetrack near you in the years to come.
The days of professional Grand Prix road racing in the U.S. are long gone. It's been almost a half-decade since we've seen the blue-tinged haze floating above the starting line at an AMA national. True, the United States Grand Prix Racers Union (USGPRU), along with scattered regional club series, have picked up some slack and still offer racing classes for those willing pre-mix contestants, but the days of small-bore GP racing are history... Or are they?
What if we told you there is a man who has tangible experience in promoting popular racing series? Ever heard of ABC's Wide World of Sports Superbikers? And what would you believe if we said there are tens of thousands of 450cc off-road bikes parked in garages all across the U.S.? And now the best part - what if you could take that existing 450cc dirt rooster that's gathering dust in your garage, install some bolt-on parts and transform it into an asphalt-carving sub-270-pound road racer?
Well, friends, the concept is more than just a fantasy - it's the idea of race promoter Gavin Trippe. Trippe first envisioned the idea over a year ago during an AHRMA vintage racing weekend in Ohio, where he witnessed racers on supermoto bikes decimating the vintage road race competition. Trippe remembers when single-cylinder bikes like Suzuki's TS250 use to be popular racing options. But after the late '70s, manufactures began to shift their focus from lightweight Singles to heavyweight multi-cylinder engine configurations. Trippe, however, held onto the classic idea and when he eventually saw a bare 450cc motocross chassis, he noticed just how similar they are to that of a purpose-built road racer.
Trippe conferred with Troy Lee of Troy Lee Designs and shortly after, the famed custom painter contacted Roland Sands Design
(RSD) to build a prototype from one of Lee's spare Honda CRF450Xs.
If there is one company which has the capability in undertaking a project such as this, it would be RSD. Roland Sands, a former AMA 250cc Grand Prix champion himself, not only knows how to throw down fast lap times on a road racer but is also renowned for inventing new motorcycle categories which synergize artistic aesthetics and racetrack-bred performance. Yet, even with Sands' eccentric bike-building capabilities, he was still skeptical.
But as Sands' team began taking measurements and grafting road race components onto the off-road chassis, they noticed just how well the street parts matched up. In fact, the chassis geometry of a modern day motocrosser is surprisingly similar to their pavement-rolling track brethren. A 54-inch wheelbase, 22.9-degree steering head angle and 98mm of trail are all numbers we would expect to see on the current crop of 600cc sportbikes.
The master of sport/cruiser fusion in the custom realm, former AMA 250GP champ Roland Sands (above) has turned his talents toward blending the off-road and road-racing worlds in the form of his new SuperSingles.
To keep fixed costs reasonably affordable, Trippe requested that Sands retain as many stock components as possible. This means that engine displacement, ignition, gearbox, frame, subframe, swingarm, and engine mounting points all remain production; leaving suspension, wheels, brakes, control surfaces and bodywork open to modification.
"We want to do everything we can to keep the frame, swingarm and engine position intact. It may not be the perfect setup but it will work for everyone and will keep costs affordable," says Trippe, whose work as a race promoter has earned him a spot in the AMA Hall of Fame.
Once the Honda
was transformed into a functional prototype, people within the motorcycle industry started taking notice. So much, in fact, that Kawasaki
supplied Sands with both bikes and parts, commissioning builds of their own. Suzuki
was the last manufacturer to jump into the SuperSingle foray when Grant Matsushima, the man behind the Matsushima Performance road racing effort assembled a prototype based off one of Kevin Schwantz's supermoto bikes. With all four bikes put together, Trippe and Sands brought the bikes out to Mazda Laguna Seca Raceway for an on-track demonstration during last year's Corona AMA Superbike season finals. And after watching the thunderous rainbow-colored quartet whiz in formation down Laguna's front straightaway, we were anxious to learn more.
With the hype surrounding these machines at an all-time high, we contacted the wrecking crew over at RSD and hauled the three of the four 450 SuperSingles out to the tight and hilly, Horsethief Mile road course at Willow Springs International Raceway for us to get our own read on these potential lightweight racing sensations.
With all three bikes one-of-a-kind prototypes, we didn't know what to expect. Just getting the single-cylinder engines to life is an experience within itself. Like a true Grand Prix bike, there is no electric start. The sleek GP-styled bodywork is in the way of the original kick-start, making the only viable option bump starting.
Strip off the fairing and the SuperSingle's motocross origins are apparent, with the dirtbike's geometry surprisingly similar to current road racing platforms.
Once started, the machines idle obnoxiously and with their rerouted undertail RSD exhaust, the bark they emit is just plain loud - more so than any factory motocross machine. A quick pump of the throttle and everyone within a 20-foot radius is either smiling or plugging their ears.
Placing a leg over the diminutive machines reveal a compact yet reasonably comfortable cockpit. Seat height is about as low to the ground as a Kawasaki Ninja 250, yet to our surprise it's not as cramped as we assumed - even for my six-foot-tall chassis. The clip-on handlebars are low and repositioned foot controls are tucked up and rearward, equating to a riding position which shows no signs of its prior life. Moving the bike between your legs is amusing as the combination of the slim twin-spar aluminum frame, low seat height, and the bike's low center of gravity make it feel almost toy-like.
However, nudging the shift lever into gear and slipping the cable-actuated clutch exposes the same torquey 450cc powerplant that the likes of Honda Red Bull's Andrew Short use in the confines of the AMA Supercross arena. Fortunately, the annoyingly loud mash of clutch slippage and 2-Stroke engine wail, typical during starting line launches is gone.
Even with the relatively mild state of tune, the 450cc engines have a decent amount of get-up-and-go, even with super-tall street gearing. Sure, there isn't going to be any power wheeling going on, but the Singles build rpm quickly and acceleration is brisk - especially when the engine is short-shifted and kept in the happy zone of its powerband. Furthermore, the engine's friendly power characteristics allow the rider to accelerate clean from any rpm and the linear power spread instills hefty amounts of confidence, allowing the rider to open the throttle much earlier and faster than they would on a multi-cylinder road racer. To an experienced middleweight rider, the power delivery is nothing astounding, but with the slower power pulses being pumped out by the 450cc Single, controllably spinning the rear Dunlop 165/55 rear slick is less intimidating and perhaps even more entertaining. With the instrument package not yet functional we aren't sure what top speeds we were hitting, but with the right gearing, the bikes should be good for around 110-120 mph.
The goal with the SuperSingle is to provide an affordable entry-level ride for aspiring racers. RSD is already accepting order for a turn-key racer based off the Yamaha WR450.
When it comes time to slow things down, the rider realizes how precious the gift of light weight is. Even with a single front disc brake, stopping power on these machines is copious. Each one of the three bikes featured unique setups consisting of either stock streetbike parts, aftermarket race bits or both. However, the common theme they all shared is: a single cross-drilled front disc matched to radial-mount four-piston caliper. Powering the setup is a radial-mount master cylinder pushing brake fluid through a steel- braided line. With the combination of sub 270-pound (fully-fueled) weight and the large contact patch provided by the 120/70 front Dunlop racing slick, trail braking at lean all through the corner is ridiculously simple.
Suspension is a hybrid blend of both street and dirt with the Honda featuring an aftermarket CBR1000RR Ohlins front end, whereas the Kawasaki and Suzuki utilize stock ZX-6R and GSX-R setups respectively. Handling rear suspension duties, both the Honda and Kawasaki employ a single Ohlins motocross shock tuned by PPS Suspension. The Suzuki retains its OE Showa piece, but it is shortened and revalved for track use.
With 11 corners in just a scant one mile, Willow's Horsethief places a real emphasis on handling. And cornering prowess is where these bikes excel. We were stunned by how quickly the bikes change direction. A light touch of the clip-on handlebar with a little bit of body English and the bike responds. Even with suspension development in its infancy, the bikes gobble up the track effortlessly, making the rider feel like they can do no wrong. Coupled with the 450s light weight and extreme agility, the rider can place the bike anywhere on track, selecting a line that normally wouldn't be possible on a bigger machine. Getting the SuperSingle turned and your knee on pavement seems almost too easy, as if someone were playing you on XBOX.
Grand Prix bikes are all about corner speed and the 450 SuperSingles are no different. At full lean, the bikes are solid and provided us with quite a bit of feedback through the handlebars and seat. This made it possible for us to carry more momentum through the corner than we would on a larger-displacement sportbike. Although the suspension setup is in no way ideal, with definite room for improvement in terms of spring rates and valving, we are impressed. The foundation and core handling fundamentals are there.
Given the relatively high levels of lean, you might expect some ground clearance issues but the only bike where it was true was the RM-Z. Due to the low position of the White Brothers muffler, a little pavement grinding occurred on the tip of the exhaust. The other two bikes' hard parts were tucked up high enough where asphalt scrapeage wasn't a concern.
Could the SuperSingle be a new entry-level support class in the AMA Superbike series?
Replacing the standard wire-spoke wheels are 17-inch tubeless aluminum hoops front and rear. The lightweight wheels keep both unsprung weight and rotating inertia low. This increases the bikes handling proficiency and allows use of the latest sized race rubber (120/70-17 front, 165/55-17 rear). The Honda and Kawasaki make use of a 3.5-inch front and 5-inch wide rear RSD "Assault" wheels, while the RM-Z rolls on the same sized black Marchesini supermoto-style wheels.
Arguably, the most important factor in determining the feasibility of this prospective racing model is cost. And price for a brand-new mass produced 450cc dirt bike is near 8-large out-the-door. Add in the price of the conversion parts and you could be spending $4000-$6000 more. And that's without even touching the engine. If you don't have that kind of dough, but are internet savvy and have decent mechanical aptitude, you can go second-hand. Buying a used late-model 450 can trim a few G's off the price of the bike. Major streetbike hard parts i.e. fork, shock, and brakes are readily available and can be sourced for a sensible price on websites such as eBay, craigslist, and internet forums, one could foreseeable piece a used SuperSingle together for less than the cost of a brand-new middleweight 600.
At this point durability of the 450 racers is still unknown. But since these off-road machines were designed to be used in a wide range of harsh environments including hot dry deserts, cold, rock-filled mountains, and soggy, rain-soaked forests, as well as harsh racetracks world wide, reliability and maintenance issues should be no worse than any other racing motorcycle - as long as the engines are kept close to stock. However, it is important to note that without a spec horsepower limit, as with any type of motorsports competition, the engines will become highly stressed pieces and if you've ever modified the insides of a 450cc thumper then you know they are subject to failure more frequently than a stocker. And when they do pop, all those parts inside aren't cheap to replace... We know first hand.
Without a doubt these bikes are a blast to ride. They really allow the rider to work on the essential techniques of road racing i.e. braking, throttle control and cornering without being overwhelmed by sheer power or outright speed. Considering that they are nothing more than a mish-mash of parts with very little actual setup time they perform amazingly well.
So what's next you ask? When can you see these contemporary 4-Stroke Grand Prix machines in action? And even more importantly - when can you get your hands on one? As of this report the plan is for a ten-race spec series to be sanctioned by WERA with hopes of it becoming an AMA recognized class in 2009. As far as where and when you can get one, RSD introduced a complete turn-key Yamaha 450 SuperSingle in late February at $14,999. And for those of you who want to build your own, RSD will have a complete product line including: wheels, brakes, foot control brackets, fairing mounts and complete bodywork kits later this year.
Hmmm... with the help of Trippe and Sands, maybe that boy racer dream isn't that impossible after all.
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