Retrospective: 1989-1993 Buell RS1200

1990 Buell RS1200
1990 Buell RS1200

Talk about making a silk purse out of a sow’s ear—that’s what Erik Buell managed to do back in the late 1980s. Now, nothing wrong with a sow having ears, all the better to hear when feeding time comes around, but when the hoglette (i.e., Harley Sportster) became a true sports motorcycle it was time to pay attention.

Back in 1986, Buell, an engineer at Harley-Davidson, decided he wanted to build a fast Harley, and found out that the Motor Co. was selling a bunch of its XR1000 engines that were being discontinued. Obviously he got a deal. The stock 1983 1,000cc V-twin was rated by Harley at an immodest 70 horsepower, but only 57 of them showed up at the rear wheel. With a little refinement from a Harley “high-performance mod kit” that figure could be upped a bit…for track use only, of course. The Buell Motor Company was incorporated in February of 1987.

1990 Buell RS1200It was the chassis that would require attention, and a very stiff, triangulated frame was created out of round alloy tubing, with all the pieces being straight, as Buell felt this would give maximum rigidity to the whole machine. His specialty was frame and suspension, and he did put together a pretty spiffy number in the RR1000 model, eligible for the AMA’s Battle of the Twins races. A full fairing completely concealed the Harley engine that Buell was so proud of, even though large letters on both sides of the fairing read “Powered by Harley-Davidson.” Dang!

Move forward to 1989, and Buell has bought some 1,200cc Evolution engines from Harley. The 1200 was a street-only engine, with everything from carburetor intakes to mufflers being determined by the feds. The new engine meant changes to the RR1000 model, so we will start from there. He began with the fully-faired RR1200, but quickly moved on to the half-faired RS1200—which allowed part of the engine to shine.

1990 Buell RS1200The vibrations of a 45-degree V-twin are considerable, and unless one goes inside the engine to build a counterbalancing arrangement, there is not much one can do. Or the rider can be isolated from the engine using rubber motor mounts, part of Buell’s patented Uniplanar mounting system. Still the engine was trying to rid itself of the jail-like chassis, so he sophisticated the design by putting in four ball-end mounting rods that would limit the shaking to a vertical plane alone—much less stressful. And smoother than any other bike using a Harley engine.

The Sportster motor was quite rudimentary, with a bore of 88.8mm, stroke 96.8mm, and pushrods operating the two valves in each cylinder. The highly recognizable oval Harley air cleaner passed air to the single 40mm Keihin CV carb, which fed the high-test gas into the engine, to be compressed nine times and ignited by a magnetically triggered spark, a.k.a. digital CDI. A SuperTrapp muffler was a bit on the noisy side, but helped to raise the engine’s power from a stock 50 to some 56 rear-wheel horsepower at 5,500 rpm, with 64 lb-ft of torque at 3,000.

1990 Buell RS1200A triple-row chain ran the power back through a wet clutch to a four-speed (later five) gearbox, then out to the rear wheel on a hefty #530 chain. The steel swingarm, a mere 16 inches long, pivoted off the gearbox, and the unconventional frame did not allow for standard shock absorbers. Instead, a Works Performance shock lay flat under the engine and worked in reverse, extending as the rear wheel rose, using tension rather than compression. That was new. The only adjustment possible was preload, requiring the owner to crawl around and fiddle the two bolts that compressed the spring. The shock was charged with nitrogen, and damping could be altered by changing the pressure of the gas—not a job that the average home mechanic might relish doing. The 4.2 inches of movement meant that smooth roads were preferable. The back wheel—both 17-inch aluminum four-spoke wheels were by Performance Machine—carried a 170/60 tire and had a 25mm axle; Buell liked strong axles, maintaining that they helped keep the chassis stiff. A single Brembo disc with a two-piston caliper helped slow things down.

1990 Buell RS1200Up front a 40mm Marzocchi fork had an electric anti-dive system put in by Buell; this was known as ACT, or Air Control Technology. The fork went down to a big 20mm axle penetrating the hub. A pair of discs with four-piston calipers (later a single disc with six-piston caliper) could slow the bike real quick. The rake on the fork was 26 degrees, with a trail of 4.3 inches, giving good stability at speed despite the 55.5-inch wheelbase. It was definitely a short bike for such a big engine.

It was the bodywork that attracted the eye of all passersby. A very short front fender showed the way to the extended nose fairing, which stretched back under the gas tank to create a smooth line going rearward to the side panels and then continuing along below the seat. But what was this contraption covering the pillion part of the seat? It was a hinged pillion backrest, so when the rider was alone the lowered backrest gave a sporty look, and then provided a secure feeling for a passenger when raised. Buell said that in his youth he once wheelied a bike and the passenger fell off; this no-fall-off backrest notion was a good idea.

1990 Buell RS1200The bikes were good, but money was always a problem, especially with the $16,000 price tag. Then in February of 1993 Harley offered to buy 49 percent of the company, and life changed for the re-named Buell Motorcycle Company. The new 1994 Thunderbolt model was a more reasonable $12,500.

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