2018 Triumph Rocket III Roadster Technical Analysis & Specification Breakdown
Built around Triumph's custom - cruiser motorcycle platform, the 2018 Triumph Rocket III Roadster relies on a 2294 cc (140 cu in) liquid-cooled in-line three, four-stroke powerplant. In factory specification, peak output is rated at 148 HP (108 kW) at 5,750 rpm while maximum torque reaches 221 Nm (163 lb-ft) at 2,750 rpm, transferring power to the rear wheel through a 5-speed gearbox and shaft drive (cardan) final drive. With a specific output of 64.5 HP per liter and a 3,000 rpm working window between peak torque (2,750 rpm) and peak power (5,750 rpm), the engine character is indicating a tractable, stress-free state of tune focused on everyday usability and broad torque delivery.
On the scales, the Rocket III Roadster measures 334 kg (736 lbs) dry, translating to a power-to-weight ratio of 0.44 HP/kg (2.26 kg per horsepower). Rider ergonomics and chassis geometry center around a 750 mm (29.5 in) seat height — giving shorter riders and urban commuters confident flat-foot reach at traffic stops, combined with a 1,695 mm (66.7 in) wheelbase engineered for planted straight-line stability. The 24-liter (6.3 US gal) fuel tank paired with a rated consumption of 8.11 L/100 km provides an estimated theoretical range of roughly 296 km (184 miles) between fill-ups.
Within MotoLibrary's Triumph archive, this model family spans 10 indexed model years from 2010 to 2019, allowing buyers to track year-over-year changes in emissions tuning, weight and equipment.
Specific Output
64.5 HP/L
Power-to-Weight
0.44 HP/kg (2.26 kg/HP)
Power Band Window
2,750–5,750 rpm
Theoretical Range
~296 km (184 mi)
Engine
Displacement2294.0 ccm (139.98 cubic inches)
Engine TypeIn-line three, four-stroke
Engine DetailsCounter rotating crankshaft
Power148.0 HP (108.0 kW)) @ 5750 RPM
Torque221.0 Nm (22.5 kgf-m or 163.0 ft.lbs) @ 2750 RPM
Compression8.7:1
Bore x Stroke101.6 x 101.6 mm (4.0 x 4.0 inches)
Fuel SystemInjection. Multipoint sequential electronic fuel injection with twin butterflies and progressive linkage on primary butterflies
Fuel ControlDouble Overhead Cams/Twin Cam (DOHC)
CoolingLiquid
Transmission
Gearbox5-speed
Final DriveShaft drive (cardan) (final drive)
ClutchWet. multi-plate
Performance
Fuel Consumption8.11 litres/100 km (12.3 km/l or 29.00 mpg)
Greenhouse Gases188.2 CO2 g/km. (CO2 - Carbon dioxide emission)
ExhaustStainless steel 3 into 1 into 2. large volume catalysts in front of chrome-plated exhaust
Use this page to compare this motorcycle by its real specifications, not only by model name. Focus on the details that affect fit, comfort, handling, range and ownership.
Power
Compare engine output with similar motorcycles if acceleration, highway use or two-up riding matters.
Torque
Torque is useful for judging real-world pull, especially for touring, commuting and loaded riding.
Seat Height
Check the seat height against your inseam and riding posture before choosing a motorcycle.
Weight
Compare weight carefully because it affects low-speed handling, parking and confidence.
Fuel Capacity
Fuel capacity helps estimate touring range and how often you may need to stop.
Brakes
Brake setup is worth comparing if you ride in traffic, mountains or with a passenger.
Suspension
Suspension details can matter for comfort, road feel and long-distance riding.
Transmission
Transmission and final drive affect maintenance, smoothness and everyday usability.
