New Buell 1125R Features & Details

Metric Thunder ReportHow Buell has Defined the American Sportbike Riding Experience

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:

      1. – Mass Centralization
      2. – Low Unsprung Weight
      3. – Chassis Rigidity

The Development Goal
The goal is 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.

Mass Centralization and achieving the optimal center of gravity makes quick direction changes seem effortless. Low unsprung weight enhances traction, maneuverability and stability and is applied in every Buell motorcycle.

Examples of the Trilogy of Tech as applied to the new Buell 1125R

  • Compact 72-degree DOHC V-Twin engine allows the engine to be located forward in the frame
  • Aluminum frame spars double as a 5.6-gallon fuel tank, to carry fuel lower on the chassis
  • Radiator location also allows the engine to be positioned further forward in the frame
  • Muffler is located below the engine, rather than high and behind the rider
  • Chassis Rigidity allows the motorcycle to hold a precise line in corners
  • The engine is solid-mounted to the frame and acts as a structural member
  • First OEM spec 47 mm inverted front forks with reduced friction seals
  • New Buell ZTL2 front brake systemis approximately six pounds lighter than twin disc brakes
  • Lightweight front wheel hub and spoke configuration reduces steering inertia
  • Rear brake caliper reducesan additional 1.5 pounds of unsprung weight

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 Engine Power
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
  • 18-degree valve angle and straight path for the down-draft intake system
  • Engine has a low-inertia flywheel for a quick-revving performance and smooth shifting
  • Engine is a stressed member of the frame and contributes to overall chassis rigidity
  • Formula 1 engine technology permits a quicker valve opening, and eliminates valve float
  • Valve covers are magnesium to reduce weight
  • Dry sump oiling reduces internal windage losses
  • Dual downdraft 61 mm throttle bodies provide superior intake air flow
  • Twin side-mounted free flowing radiators are mounted longitudinally within aerodynamic cowlings
  • ECU controls the TPS, IAC, and monitors engine performance while continually adjusting
  • Ram-air system pressurizes the air box for a gain in peak performance

Buell finally gets liquid cooling in the Buell 1125R Superbike, an all-new high-performance sportbike powered by an 1125cc liquid-cooled V-Twin engine.

Chassis and Suspension Features

  • All-new Buell IRC (Intuitive Response Chassis) is the stiffest chassis ever offered
  • Aluminum frame spars double as a 5.6-gallon fuel reservoir
  • A fully-adjustable Showa rear shock/spring unit
  • Fully-adjustable Showa 47mm inverted front forks and new triple clamps
  • 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
  • The caliper casting was optimized for clamping stiffness
  • The rear brake utilizes a 240 mm stainless steel rotor gripped by a two-piston caliper
  • Rear caliper is mounted to the inner surface of the swing arm & is hidden from view
Clutch and Transmission Features
  • HVA (Hydraulic Vacuum Assist) Slipper Action clutch
  • A six-speed, close-ratio transmission
  • A Goodyear Hibrex final drive belt
  • Gear ratios were selected for optimal power band at typical operating speeds


  • Quiet Zone cockpit aerodynamics were developed from computational fluid dynamics models
  • The fairing and windshield optimize air flow over and around the rider for reduced drag
  • 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

Buell finally gets liquid cooling in the Buell 1125R Superbike, an all-new high-performance sportbike powered by an 1125cc liquid-cooled V-Twin engine

Rider Interface

  • An athletic rider position with a foot peg location that provides 50-degree lean clearance
  • 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
  • (Onboard Diagnostic Information System) displays service codes
  • Four-digit security code system immobilizes the ignition

Buell finally gets liquid cooling in the Buell 1125R Superbike, an all-new high-performance sportbike powered by an 1125cc liquid-cooled V-Twin engine.

About Buell Motorcycle Company
Buell Motorcycle Company, a subsidiary of Harley-Davidson, Inc., produces premium sport performance motorcycles, motorcycle parts, accessories and apparel. To learn more about Buell motorcycles, visit your local Buell dealer and experience the aggressive attitude, style and performance only found on board a Buell. For the Buell dealer nearest you, pull into

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