but varies less than of torque from 3,000 to 10,500 rpm. There is a vacuum assist slipper clutch to give predictable drive performance in hard cornering and deceleration and a six-speed transmission. The Helicon engine was developed and built by BRP-Powertrain in Austria. The design had significant Buell input and was funded through Buell's cashflow. The 1125R did not have a full fairing, as that would have put it in the same class as Japanese sportbikes. Erik Buell agonized over this, saying "it's not about listening to the voice of the customer." Cycle World magazine said the 1125R was "a bit of an oddity." The bike was initially released with a crude spark map, leading to criticism of the bike at low speeds. The Rotax Helicon also ended up costing significantly more by production time due to fluctuation in exchange rates. 1125CR For the 2009 model year, Buell introduced the 1125CR, a version of the 1125R in the cafe racer style. This was done in response to customer feedback, which said the 1125R wasn't what was wanted, and causing Buell to shelve plans for a Streetfighter, going for a cafe racer instead. The 1125CR has a longer swingarm, a longer wheelbase and a shorter secondary drive ratio. Racing Buell XBRR Buell also produced a limited series of 50 XBRR (, ) racing-only machines for factory-backed and privateer racing teams. The XBRR frame was a XB1/XB2 hybrid, the suspension came from Swedish manufacturer Öhlins, and the wheels were made of magnesium. It was the first model using the ZTL2 eight-piston caliper by Nissin. Buell 1125RR In 2009, Buell announced production of the 1125RR, also a race-only motorcycle. The bike was internally called the B2, aimed for the supersport market. Built from the 1125R, the 1125RR changes include a titanium exhaust, magnesium wheels, full fairings and a chain drive. On September 9, 2009, Buell won its first AMA Pro racing championship. Rider Danny Eslick clinched the title at New Jersey Motorsports Park on Buell's 1125R model. On November 15, 2009, Buell won its first NHRA Pro Stock Motorcycle world championship. Rider Hector Arana clinched the title at Southern California NHRA Finals on a Lucas Oil backed Buell. References External links Defunct motorcycle manufacturers of the United States Motorcycles introduced in the 1980s Vehicle manufacturing companies established in 1983 Vehicle manufacturing companies disestablished in 2009 1983 establishments in Wisconsin 2009 disestablishments in Wisconsin