The ulcers keep piling on for the warden of the MotoUSA asylum. With the inmates running rampant around the globe, Hutch has opted to get in on the madness more these days than in years past and is back in the saddle again.
Utilizing the Buell Trilogy of Tech principles and computer-modeled aerodynamics, the 1125R is designed to deliver the precise handling that has defined Buell for 25 years with a new level of engine performance.
The 25th Anniversary of the Buell Motorcycle Company coincides with a new chapter in the history of America’s largest manufacturer of sporting motorcycles: A liquid cooled 72-degree 1125cc motor powering its all new 2008 Buell 1125R.
At the heart of the 1125R is the Helicon V-Twin powerplant, claimed to produce 146 horsepower at the crank, developed in conjunction with BRP-Rotax specifically for Buell and the 1125R. Buell fans can rest assured that the bike is true to the Buell heritage of being rider friendly and decidedly different than the competition. The fuel-in-the-frame technology is retained, although capacity has been raised to 5.6 gallons. It’s still-stubby 54.5-inch wheelbase is 2.5-inches longer than the current Firebolt design and should still be plenty agile. The next generation of the Zero Torsion Load single-disc front braking system, ZTL2, features an 8-piston caliper derived from the XBRR racing platform and should provide plenty of power to haul this beast down from speed.
After years of riding and enjoying Buell motorcycles, the primary complaint from this company and the majority of the motorcycle media was a decided lack of power compared to the competition. Buell appears to have addressed this issue and with the track introduction of this new bike just weeks away, the answer to some of the questions on the minds of consumers everywhere will soon be answered.
Will the bike be as powerful as Buell claims? Will it still have that razor-sharp handling of its predecessors? Will the chassis be stable enough to handle the additional speed facilitated by the new motor? How will this version perform on the race track? How will it stack up to the other V-Twin liter bikes? We should have answers to all of these except the last question by the end of August.
Quiet Zone cockpit aerodynamics were developed using computational fluid dynamics (CFD) models and experience gained in development of the Buell XBRR production racing motorcycle. The shape of the fairing and windshield optimize air flow over and around the rider for reduced drag and enhanced rider comfort.
For now, images and video will have to keep our palette whet while we await the opportunity to actually ride them. The bike resembles the XBRR race machine sans body panels, albeit’s equipped with road-ready amenities like a tidy new dash board, clean tail section and pillion accommodations, slick looking underslung exhaust, and integrated blinkers. They didn’t forget the slipper-type clutch either.
“We designed the 1125R from the rider down,” said Erik Buell, chairman and chief technical officer at Buell Motorcycle Company. “The 1125R takes Buell to a new level of performance, while continuing to embrace the fundamental Buell principals of motorcycle design and offering a great motorcycle riding experience.”
The Helicon Engine The Buell 1125R Helicon engine is a high-performance, 72-degree DOHC liquid-cooled V-Twin specified by Buell and designed in collaboration with BRP-Rotax, one of the premier recreational-engine manufacturers in the world. Buell provided a detailed specifications list to BRP-Rotax, outlining powertrain requirements to meet the performance goals of the Buell 1125R. Buell also directly contributed technology and engineering on a number of key areas, including the compensating front sprocket, transmission layout, the shift mechanism, engine cases, pistons, intake, exhaust, and new DDFI 3 EFI system. All major components of the Helicon engine are unique to Buell and developed specifically for the Buell 1125R, although a few components, such as the stator and various fasteners, are used in other BRP-Rotax products. The new Helicon engine will remain exclusive to Buell. The Helicon engine will be assembled by BRP-Rotax in Austria. The Buell 1125R motorcycle will be assembled by Buell in East Troy, Wisconsin. Its V-Twin design perpetuates the look, sound and character that have always help to define the Buell riding experience.
The motor’s 72-degree V-angle provides a steep 18-degree valve angle and straight path for the down-draft intake system. This layout is a very compact case and cylinder head design which allows the engine to be located far forward in the chassis, distributing 54 percent of the vehicle weight on the front tire.
Rather than design the Helicon engine to fit a specific displacement category or racing classification, Buell developed this powertrain to meet a customer experience specification, both in terms of its power output and its contribution to the overall performance of the Buell 1125R. The engine produces 146 crankshaft horsepower at 9800 rpm and 82 ft. lbs. of peak torque at 8000 rpm. Redline is 10500 rpm. Its generous 1125cc displacement allows the Helicon engine to make abundant peak power with a broad powerband and flat torque curve free of dips and weak spots. The Helicon engine is designed to make useable power across the entire RPM range that will enhance any riding experience.
Helicon engine features: 72-degree cylinder angle and a very compact case and cylinder head design allow the engine to be located far forward in the chassis, distributing 54 percent of the vehicle weight on the front tire.
The 72-degree V-angle provides a steep 18-degree valve angle and straight path for the down-draft intake system.
A cylinder angle of 72 degrees reduces shaking forces. The engine is also fitted with three balance shafts: two balancers for canceling primary rotating imbalance and a third balancer for canceling the rocking couple.
The displacement of 1125cc was chosen to create an optimal 103.0 mm bore x 67.5 mm stroke configuration – generous bore for more valve area and better breathing and short stroke for reduced friction, increased rpm range and instant throttle response.
The engine has a low-inertia flywheel for a quick-revving performance and smooth shifting. The engine is a stressed member of the frame and contributes to overall chassis rigidity. The swing arm pivot is located in the engine cases providing optimal pivot location and adding to overall chassis rigidity.
The muffler is tuned to produce a linear horsepower and torque curve without the added cost, weight and complexity of an active exhaust system. A Helmholtz chamber within the muffler further reduces noise output. Twin brushed stainless exhaust outlets produce less exhaust noise than a single side-mounted outlet.
Dual overhead cams with self-adjusting chain drive on each cylinder to the intake cam and gear drive from the intake to the exhaust cam. This design requires less space over the cylinder head than a two-sprocket design, allows the engine to be located further forward, and reduces engine weight.
Valves are actuated with finger followers and adjusted with shims, a design derived from Formula 1 engine technology.
Finger follower valve actuation reduces friction, permits a quicker valve opening, and eliminates valve float. This design also allows a steep valve angle of 18 degrees and a downdraft fuel injection system. The design of the follower retention system makes shim replacement quick and easy, reducing maintenance costs. Valve covers are magnesium to reduce weight.
Primary balancing with three internal shafts reduces chassis weight by minimizing vibration isolation requirements.
Dry sump oiling reduces internal windage losses. An integrated oil reservoir is located in the lower left side of the crankcase casting to lower the center of gravity and help keep the engine compact.