Buell 1125R / 1125CR Service Manual (2009)

Buell launched the 1125 platform for the 2008 model year with the 1125R, marking a major break from the company’s earlier air-cooled, Harley-Davidson-based performance motorcycles. The 1125R was conceived as a true superbike platform and introduced a purpose-developed 1,125 cc liquid-cooled 72-degree V-twin created with BRP-Rotax. Buell retained its established “Trilogy of Technology” philosophy—mass centralization, low unsprung weight and chassis rigidity—but applied it to a much more powerful and technically advanced motorcycle. Contemporary Buell launch material described the 1125R as a new third platform alongside the XB and Blast ranges, intended to balance street and track performance.

The Helicon engine defined the character of the 1125 family. It used dual overhead camshafts, four valves per cylinder, a 103.0 × 67.5 mm bore and stroke, 12.3:1 compression and Dynamic Digital Fuel Injection III. Buell claimed 146 horsepower for the platform, a substantial step beyond its previous production engines. The engine was integrated tightly into an aluminum fuel-in-frame chassis, with a dry-sump lubrication system, six-speed transmission and hydraulic vacuum-assist slipper clutch. That package made the 1125 range a distinctive liquid-cooled American superbike rather than an evolution of the older XB powertrain.

For 2009, Buell expanded the platform with the 1125CR, a stripped-back café-racer/streetfighter interpretation of the same mechanical package. The 1125CR replaced the 1125R’s full fairing with a compact headlamp and flyscreen, used a clubman-style handlebar and adopted shorter final-drive gearing for stronger acceleration. The 1125R remained the fully faired sport model. Buell also revised both 2009 models with targeted fuel injectors, relocated oxygen sensors, updated fuel and ignition mapping, a higher-output charging system and a gear-position display. The 1125R and 1125CR therefore shared the core engine, frame, suspension and brake architecture while differing in bodywork, ergonomics and final-drive gearing.

The chassis remained one of the platform’s defining elements. The 2009 machines used an aluminum frame that also served as the fuel tank, fully adjustable 47 mm inverted Showa forks, a fully adjustable rear shock and Buell’s large perimeter-mounted ZTL2 front brake with an eight-piston caliper. Factory specifications list a 1,387 mm wheelbase, 775 mm seat height, 20.1-litre fuel capacity and 206 kg wet weight. Harley-Davidson’s official service-information portal documents the 2009 1125R and 1125CR model codes, drivetrain ratios and shared 1,125 cc Helicon specification: 2009 Buell 1125 Models Owner’s Manual.

The 1125 platform’s road-going life was brief. Harley-Davidson announced in October 2009 that it would discontinue the Buell product line, with production ending that month. The 1125R and 1125CR nevertheless became the technological bridge to Erik Buell’s later racing and 1190-series development. This product is specifically the 2009 factory service manual, publication 99491-09Y, covering 2009 1125R and 1125CR models; the 2008 1125R uses separate factory publication 99491-08Y. Related material is grouped in the Buell 1125 service manual catalog.