|
- Considering that 2008 is only the company’s 25th anniversary, that’s no mean achievement. But what really distinguishes this model year and the 1125R that is born into it, is the use—for the first time—of a non-Harley-Davidson-sourced engine. Instead, the new bike is powered by a bespoke V-twin engine from BRP-Rotax, makers of recreational engines for a vast range of products. Called the 1125 Helicon, the Austrian-built V-twin engine produces 146 horsepower at 10,500 rpm, with 82 pound-feet of torque at 8,000 rpm.
Long before the partnership with Rotax evolved, Erik Buell asked his parent company if they were interested in developing a high-tech engine for his new sportbike project. Although it was, Harley-Davidson simply did not have the time to undertake a project like this alongside the many tasks already on its schedule.
That left Buell looking for a supplier, and after consulting various vendors, the company settled on Rotax. Erik Buell liked the company’s honesty. “We asked the engineers about some of the engines they’d produced in the past, and they were completely candid about things they would have preferred to do differently,” he says.
This lack of spin on the part of Rotax personnel convinced Erik Buell that the company could stay in step with his own original and innovative vision. From what we experienced of the new machine during a two-day road and track ride in Monterey, California, it seems to have been a near-perfect marriage.
The focus of the new machine’s development was on what Buell calls his trilogy of technology. That is, mass centralization, chassis rigidity, and low unsprung weight. The 72-degree dual-cam V-twin is a compact unit mounted well forward in the frame to put more weight on the front wheel. Beefy aluminum frame and swingarm components form a rigid chassis, while the huge front frame spars act as a fuel reservoir, keeping the weight low and well forward.
A pair of aluminum radiators is mounted on the side of the bike in cowlings that look like part of the bike’s upper fairing, and the bike’s muffler is slung under the machine. In the interests of low unsprung weight—which reduces the amount of work the suspension has to do to control wheel motions—the1125R makes use of the Buell zero-torsional-load front-brake system, where the brake rotor is attached to the outside of the wheel rim instead of to the hub, thereby channeling brake forces generated by the eight-piston caliper directly to the wheel instead of through the wheel spokes. That allows the use of a lighter wheel.
The bike’s final drive is by belt rather than the chain you find on most sportbikes, and that reduces the weight on the rear wheel too, not only because the belt is lighter than a chain, also because the drive train compensator (often called the cush-drive) is in the engine pulley rather than on the rear wheel.
Additionally, the rear brake caliper is mounted directly to the rear swing arm. All this obsessive attention to detail has resulted in a machine quite unlike those from other manufacturers. When Buell’s engineers discovered that a wider nosecone fairing controlled airflow over the rider better than narrower designs, and reduced buffeting, they went with it despite the slightly disproportionate face it gives the bike.
It’s in keeping with an approach that company spokesman call “from the rider down”, meaning that they’d rather do things that benefit the rider than simply follow convention. As you can see, the philosophy has resulted in a highly unusual motorcycle.
But it’s a bike that is deceptively easy to ride. The broad spread of power makes the 1125R responsive at any engine speed, with a linear increase in power that allows riders of varying experience to ride at a level that feels comfortable to them. The reduction of unsprung mass has allowed suspension settings of moderate firmness, providing good roadgoing compliance, yet the use of multi-adjustable Showa suspension components means you can also set the bike up for maximum control on a track day.
|
|
|
- Buell’s peculiar insistence on original engineering solutions has led to the adoption of a vacuum-operated slipper clutch, where a depression in the intake manifold on engine overrun provides some disengagement force to the clutch pack. That means when you shut the throttle and brake for an upcoming corner, the intake manifold vacuum allows the clutch to slip during the inevitable downshifts that follow as you set up for the turn, reducing rear-wheel drag.
Because the tight vee-angle engine design adopted for its packaging benefits results in less than optimal vibration characteristics, Buell specified no fewer than three counter-balance shafts; two for the first-order vibes that afflict non-90-degree V-twins, and one for the rocking couple produced by having both cylinders connected to a single crankpin. These have all been incorporated in ingeniously compact style, in particular the rocking-couple balance shaft, which is integral to the water-pump drive shaft.
Still, rev the bike hard as you negotiate the unusual layout of the Mazda Raceway at Laguna Seca in Monterey, California, and a fairly profound buzz sets up in the footpegs. Mind you, this is at 9,000 rpm or more, when the intense vibes are mere accompaniment to vivid acceleration. At that point, the rider usually has more on his mind.
With a reasonable riding position that facilitated a long street ride without discomfort the day before, the 1125R still permits a fully tucked-in racing position on the track, and its carefully tuned dimensions and geometries lend a very reassuring stability at speed. Buell’s engineers shunned a steering damper in keeping with Erik Buell’s belief that a good chassis ought to be able to damp unwanted resonances.
But the stout Rotax motor’s exertions pick the front wheel up under hard acceleration. That exaggerates any death grip the rider may have on the bars, shaking the bike’s head in a fairly decisive fashion and making some riders wish for a damper. I was not the fastest rider there, so I can’t be sure, but it felt to me that a light touch at the front end would allow the bike’s natural damping to quell the shakes.
One thing for sure. The 1125R gets around a racetrack like it was to the manner born. There’s a lot of cornering clearance, and the Pirelli Corsa III tires (essentially the same dual-compound items used in World 600 Superstock racing) have plenty of stick. It wasn’t long before the corner exits at Laguna were striped with Pirelli “darkies”.
Watching the bikes circulate the track, one couldn’t help contemplate the deep V-twin rumble and admire the new Buell’s agility. And one had to reflect on how a liquid-cooled Rotax engine suddenly changes the whole prospect of Buell ownership. Many of us have felt in the past that the use of Harley engines contradicted the entire concept of a sport motorcycle. Now that the 1125R is a technological (and spiritual) equivalent to an Aprilia or Ducati, its viability in the marketplace (particularly at $11,995) takes on an altogether different complexion.
For those inclined to buy American, this is very good news.
|
|
|
FOR MORE INFORMATION ON THE 2008 BUELL 1125R PLEASE VISIT - www.buell.com
|
|
PHOTO CREDIT - RILES & NELSON / KEVIN WING
|
|
|
|
|
