The Buell Motorcycle Company is set to break the convention of the superbike category with the Buell 1125R, an all-new, liter-class motorcycle that delivers an artful balance of street and track performance. Rooted in the core design principles and character that have defined Buell motorcycles for 25 years, the 1125R offers power, handling and agility that will take its owner to a new level of riding experience.
The Buell 1125R joins the XB and Blast as a third and distinct Buell motorcycle platform. The Buell 1125R is expected to arrive in Buell dealerships in late 2007.
"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 Buell 1125R riding experience derives not just from its power, but from a carefully considered combination of engine performance, precise-and-agile handling, advanced aerodynamics, and superior rider environment and control, all packaged with distinctive styling that leaves many of the motorcycle’s mechanical components exposed.
New V-Twin Muscle
2008 Buell 1125R
The Buell 1125R Helicon engine is a new 1125cc DOHC V-Twin, the first liquid-cooled engine to power a street-legal Buell motorcycle. This compact, 72-degree engine is the result of a collaboration between Buell and BRP-Rotax, a leader in the development and manufacture of advanced engines for recreational products. The Helicon engine was designed to Buell specifications and is exclusive to Buell. It will be manufactured in Austria by BRP-Rotax. The most-powerful street-legal engine ever offered by Buell, the Helicon engine is rated at 146 crankshaft horsepower, and is designed to deliver optimized usable power, with a broad powerband across its 10500 rpm range. Its V-Twin design retains the styling and character that has always defined the Buell riding experience.
The engine is cradled in a new Buell Intuitive Response Chassis (IRC) with massive, rigid aluminum spars that double as the fuel reservoir. The new 1125R sticks to the three tenets of the Buell Trilogy of Technology – chassis rigidity, low unsprung weight and mass centralization – to deliver race-inspired agility and handling. The all-new front fairing and radiator cowling was developed using the latest computational fluid dynamics (CFD) models to provide superior aerodynamics, rider comfort, and efficient air flow to longitudinal radiators and a ram-air intake system.
The front wheel is supported by 47 mm inverted forks. A new Buell ZTL2 front brake features an eight-piston caliper based on the brake developed for the Buell XBRR racing motorcycle. A smooth-shifting six-speed transmission is mated to a new HVA (Hydraulic Vacuum Assist) Slipper Action clutch that uses engine vacuum to boost clutch-lever action and to provide a "slipper" effect when the engine is down-shifted at speed. A new underslung muffler has dual brushed stainless steel outlets.
The Buell 1125R offers an athletic riding position. Quiet Zone aerodynamics are achieved by managing air flow around the rider for enhanced performance and comfort. The toe levers on both the brake and shift foot controls are adjustable to match rider foot size. The instrument cluster features a large analog tachometer and a digital speedometer, plus an Onboard Diagnostic Information System (O.D.I.S.) screen and other interactive features. The fairing shape is inspired by the Buell XBRR and features six-bulb headlamps. LED turn signals are integrated into the mirror housings.
The Buell 1125R represents an all-new platform from the Buell Motorcycle Company that is changed in almost every respect from previous Buell models, but stays true to Buell’s design and engineering philosophies. Although some of these ideas go against the conventional wisdom of the category, their steadfast application results in a motorcycle that delivers outstanding power, handling, comfort and convenience; a motorcycle that will deliver an exceptional rider experience.
The Buell 1125R joins the XB and Blast as a third and distinct Buell motorcycle platform. The Buell 1125R is expected to arrive in Buell dealerships in late 2007.
Trilogy of Technology: The Gospel According to Erik
The three legs of the Trilogy of Technology underpin every aspect of design at Buell Motorcycle Company: Mass Centralization, Low Unsprung Weight and Chassis Rigidity. The goal is always to create a motorcycle that handles intuitively, and that predictably and accurately responds to input so that the bike behaves as an extension of the rider. Here are some examples of the Trilogy of Tech as applied to the new Buell 1125R:
Mass Centralization and achieving the optimal center of gravity makes quick direction changes seem effortless.
Compact 72-degree DOHC V-Twin engine places more engine mass along the centerline of the motorcycle, and allows the engine to be located further forward in the frame.
Massive aluminum frame spars double as a 5.6-gallon fuel reservoir, to carry fuel lower on the chassis.
Radiators are mounted longitudinally between the front wheel and the frame. This radiator location also allows the engine to be positioned further forward in the frame.
The muffler is located below the engine, rather than high and behind the rider.
Chassis Rigidity allows the motorcycle to hold a precise line when it is subjected to side-loads in corners.
A new-generation Intuitive Response Chassis (IRC) is optimized for torsional stiffness.
The engine is solid-mounted to the frame and acts as a structural member.
The swingarm pivot point is located in the engine case structure, creating a more-rigid connection between the front and rear wheels.
First OEM spec 47 mm inverted front forks with reduced friction seals are secured in rigid triple clamps.
Low Unsprung Weight enhances traction, maneuverability and stability.
New Buell ZTL2 front brake system, utilizing a single disc and new cast caliper assembly with four pads, is approximately six pounds lighter than twin disc brakes.
The New Buell ZTL2 front brake transmits forces from the rotor directly to the rim, so torsional load acting on the rest of the wheel is virtually eliminated. This permits the use of a very lightweight front wheel hub and spoke configuration that reduces steering inertia.
The rear brake caliper is mounted directly to the swing arm eliminating the typical brake carrier and an additional 1.5 pounds of unsprung weight.
A reinforced Goodyear Hibrex final drive belt with Flexten Plus technology weighs just 1.06 pounds, compared to drive chains that weigh four to five pounds.
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.
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.
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.
Buell DDFI3 EFI is a closed-loop system for precise mixture control, resulting in smoother throttle operation and better fuel economy. Dual downdraft 61 mm throttle bodies provide superior intake air flow. A new ECU controls the TPS, IAC, and monitors engine performance while continually adjusting to the environment.
Ram-air system pressurizes the air box for a gain in peak performance. The air intake is located between the front fork legs and below the fairing. Air flow to this area and the size and shape of the intake were optimized using computational fluid dynamics (CFD) models. The 12-liter airbox is designed to accommodate a large air filter and to be easy to service.
Twin side-mounted free flowing radiators are mounted longitudinally within aerodynamic cowlings. The position of the radiator system lowers the center of gravity and centralizes mass, and allows the cowlings to direct free-flowing air to each radiator. The cowlings have an internal vane (splitter) to split airflow efficiently and were designed with computational fluid dynamics (CFD) models to optimize air flow at all speeds and to create a pressure differential around the radiator to pull air through the core. Hot air is also exhausted away from the rider for enhanced comfort.
The exhaust system features a large-volume muffler mounted below the engine to optimize cg location and mass centralization. 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.
2008 Buell 1125R
Chassis and Suspension Features
An all-new Buell IRC (Intuitive Response Chassis) is made in the USA and is the stiffest chassis ever offered by Buell. Its rigidity is aided by the engine, which is a rigid stressed member of the chassis. The inner frame incorporates air-flow channels that create a low-pressure area behind the engine to draw hot air out the rear of the motorcycle. Utilizing patented Buell Fuel in the Frame technology, the aluminum frame spars double as a 5.6-gallon fuel reservoir.
The stiffness of a new cast-aluminum swing arm has been tuned for the 1125R. The pivot point of the cast-aluminum swing arm is located in the engine cases to create a more rigid connection between the rear wheel, the frame, and the front wheel. By placing the swing arm pivot point forward in the engine cases, the anti-squat properties and suspension control of the 1125R were optimized. The rigid connection to the engine was used to optimize the stiffness of the swing arm in relation to the overall chassis.
A fully-adjustable Showa rear shock/spring unit features an external piggyback reservoir for good heat dissipation. To reduce weight, the shock is mounted directly between the frame and the swingarm without linkage, and its off-center placement optimizes airflow through the motorcycle.
Fully-adjustable Showa 47mm inverted front forks and new triple clamps stiffen the torsional response of the front end and improve steering response. A new fixed bushing slides against the hard-chrome surface of the fork tube, reducing friction. Compression adjustment can be made with a simple hex-key tool.
Wheelbase is 54.5 inches, rake is 21 degrees and trail is 3.3 inches.
Brake System Features
New Buell ZTL2 (Zero Torsional Load) front brake utilizes an eight-piston caliper based on a design developed for the Buell XBRR production racing motorcycle. The eight-piston design offers a larger pad surface, optimizes heat-dissipation capability and allows even pressure distribution over each of the four pads in the caliper.
The caliper casting was optimized for clamping stiffness, yielding a more progressive and connected braking feel to the rider. A single 375 mm stainless steel rotor is mounted directly to the wheel rim. This design produces outstanding stopping power and weighs less than a dual-disc system. And because braking forces are transmitted directly from the rotor to the rim, torsional load acting on the rest of the wheel is virtually eliminated. This permits the use of a very lightweight front wheel that also helps reduce steering inertia.
The rear brake utilizes a 240 mm stainless steel rotor gripped by a two-piston caliper. The caliper is mounted directly to the inner surface of the swing arm, so it is hidden from view and also weighs 1.5 pound less than a typical rear-brake design.
Front and rear brakes are fitted with braided steel brake lines for optimal feel and braking performance.
The front brake hand control is adjustable for reach. The rear brake foot control is adjustable for reach, and the toe piece is adjustable to match rider foot size.
Clutch and Transmission Features
HVA (Hydraulic Vacuum Assist) Slipper Action clutch features hydraulic actuation from the hand control with assistance from engine vacuum for lighter clutch effort. The vacuum assist also produces the same effect as a "slipper" clutch for more controlled engine braking during high-speed downshifts.
A six-speed, close-ratio transmission is an oblique stacked configuration that is tilted to minimize overall powertrain length and allows the engine to be optimally placed within the chassis. Gear ratios were selected to allow the engine to remain within its optimal power band at typical operating speeds.
A Goodyear Hibrex final drive belt with Flexten Plus technology weighs just 1.06 pounds, compared to drive chains that weigh four to five pounds. The belt system is clean, quiet and extremely strong.
2008 Buell 1125R
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.
Computational fluid dynamics (CFD) models were also used to design the efficient, aerodynamic shapes of the radiator cowlings, which direct radiator heat away from the rider.
The fairing incorporates a six-bulb headlight system for brilliant road illumination at night. Two bulbs are illuminated in daylight running mode for enhanced visibility in traffic.
LED turn signals are incorporated in the aerodynamic mirror housings where their placement and brilliance are more visible to other drivers.
The Buell 1125R offers an athletic rider position with a foot peg location that provides 50-degree lean clearance in cornering situations.
Quiet Zone cockpit aerodynamics optimizes air flow around the rider.
Brake and clutch hand controls are adjustable for reach.
Foot controls (brake and shifter) feature toe pegs that adjust to rider foot size.
Wiring harness is pre-wired for accessory heated hand grips.
Instrument cluster features:
Large analog tachometer
Digital speedometer on an LED screen visible within a 50-degree angle of view
ODIS (Onboard Diagnostic Information System) displays service codes
Four-digit security code system immobilizes the ignition
Lap timer and splits
Ambient air temperature
Two trip odometers
nstantaneous miles per gallon
Average miles per gallon
Low fuel indication with trip count
Buell 1125R Colors Bodywork: Midnight Black Wheels: Diamond Blue Frame and Swingarm: Diamond Blue Engine Trim: Fusion Bronze
Engine Engine: Liquid-cooled, 4-stroke, 72° V-Twin Valve Train: Dual OHC, 4 valves per cylinder, finger follower design & shimming Bore x Stroke: 4.055 in. x 2.658 in. (103 mm x 67.50 mm) Displacement: 68.70 cu. in. (1125 cc) Compression Ratio: 12.3:1 Fuel Delivery: Dual 61 mm down draft throttle bodies, DDFI III fuel injection Intake: Zero-resistance airbox, Pressurized RAM air intake Exhaust: Tuned, tri-pass resonance chamber with intergal helmholtz tuning and mass centralized mounting Torque (North America per SAE J607): 82 ft. lbs. (111 nm @ 8000 rpm) Horsepower (North America per SAE J607): 146 hp @ 9800 rpm Lubrication: Dry-sump with integrated oil reservoir in lower crankcase Oil Capacity: 4 qts. (3.8 L) Oil Filtration: Disposable cartridge
Drivetrain Primary Drive: Helical Gear, 0.554:1 36/65 ratio Final Drive: Constant path, 14 mm pitch aramid-reinforced Goodyear Hibrex belt with Flexten Plus technology, 2.593:1 (70/27) ratio Clutch: Wet, multi-plate, Hydraulic Vacuum Assist (HVA) slipper-action clutch, hydraulic clutch lever effort Transmission: 6-speed, straight cut gears Gear Ratios:
Chassis Frame: Aluminum frame, fuel in frame Front Fork: 47 mm Showa inverted forks with adjustable compression damping, rebound damping and spring preload Rear Shock: Showa coil-over monoschock with external piggyback reservoir and adjustable compression damping, rebound damping and spring preload Wheels: Diamond Blue
Front: 6-spoke, ZTL2 cast aluminum, 3.50 in. x 17 in. (89 mm x 432 mm)
Rear: 6-spoke, ZTL2 cast aluminum, 5.50 in. x 17 in. (140 mm x 432 mm)
Rear: Two-piston, direct mount caliper; 240 mm, stainless steel, fixed rotor
Front Wheel: 4.72 in. (120 mm)
Rear Wheel: 5 in. (127 mm)
Electric Battery (per Battery Council International Rating): Sealed lead acid, maintenance-free, 12V, 12-amp/hour, 200 cca Charging: 32-amp, permanent magnet, three-phase, solidstate regulator (432W @ 7000 rpm, 432W peak) Starting: 900W electric with one way clutch Lights (as per country regulation): Headlamp (six-bulb headlamp system with daylight running mode, 35-watt [H8]): 70-watt low beam (two bulbs,35-watt each), 140-watt high beam (70-watt low beam with two additional bulbs,35-watt each) Tail / Stop Lights: 5W/21W Turn Signal Lights: LED manual canceling License Plate Light: 5W
Instrument cluster with ODIS (Onboard Diagnostic Information System) featuring analog tachometer with integrated shift light, digital speedometer on LED display, odometer, ODIS service code display, 4-digit security system with ignition immobilizer, lap timer (records up to 99 lap times) and splits, ambient air temperature, coolant temperature, average and instantaneous fuel consumption, miles to next service display, low fuel (plus miles traveled on reserve); high beam, neutral, turn signals; clock