Triumph Rocket III

The Triumph Rocket III is a British motorcycle made by the Hinckley Triumph factory and has the largest displacement engine of any mass production motorcycle in the world (as of September 2008), at 2,294 cc (140.0 cu in). The shaft driven Rocket III produces 200 N·m (150 ft·lbf) @ 2,500 rpm and 140 bhp (100 kW) @ 6,000 rpm. Despite its size and weight of 704 lb (319 kg) dry, it is described as having good balance and "light and easy steering" even at low speeds.

Competition

Part of the reason for the secrecy was competition from other manufacturers. Yamaha launched the 1,670 cc (102 cu in) (badged as a 1,700 cc) engine in 2002 with the introduction of the Road Star Warrior and Honda launched the VTX1800, so a decision was made to go for a displacement of 2,294 cc to see off the competition.

Engine development

The first engine was built in summer 2002 and tested in the autumn. Twin butterfly valves for each throttle body were used to increase control and allow the ECU to vary the mixture flow and ignition map according to the gear selected and speed. The torque curve is modified for each gear ratio, enabling over 90% of the engine’s torque output at 2,000 rpm, giving the high levels of flexibility that the designers needed. The 1,500 W starter motor on the Rocket III puts out as much power as the engine on the very first Triumph motorcycle, Siegfried Bettman's 1902 1.75 horsepower (1.30 kW) single. When the development team were dyno testing the prototype engine it put out so much heat the whole exhaust system was glowing red.

Road testing

Road tests proved that the 0–60 mph (0 97 km/h) time was quicker than most sport bikes and the weight distribution, low centre of gravity and geometry made handling easy with acceleration up to 135 mph (217 km/h). In 2004, the Rocket III set the world land speed record for a production motorcycle over 2000 cc reaching its electronically set limiter of 140.3 mph (225.8 km/h).

Launch

2004 NEC Motorcycle show launch

In 2003, the prototype was renamed the 'Rocket', following extensive market research, continuing the successful approach of linking back to the heritage of famous British motorcycles. It was unveiled in the USA on 20 August 2003, in San Antonio, Texas, during the annual US dealer conference.

Triumph Rocket III

Manufacturer	Triumph
Production	since 2004
Engine	2,294 cc (140.0 cu in) DOHC liquid-cooled inline three-cylinder
Power	140 bhp (100 kW) @ 6,000 rpm
Torque	200 N·m (150 ft·lbf) @ 2,500 rpm
Transmission	Gear (Primary) / Shaft (final drive)
Wheelbase	1,695 mm (66.7 in)
Dimensions	L 2,500 mm (98 in) W 970 mm (38 in)
Seat height	740 mm (29 in)
Weight	704 lb (319 kg) (dry), 774 lb (351 kg) (wet)
Fuel capacity	24 l (5.3 imp gal; 6.3 US gal)