Built around Enfield's classic motorcycle platform, the 2011 Enfield Thunderbird TwinSpark pairs a 346 cc (21.1 cu in) air-cooled single cylinder, four-stroke architecture with road-focused gearing. In factory specification, peak output is rated at 19.8 HP (14.5 kW) at 5,600 rpm while maximum torque reaches 28 Nm (20.7 lb-ft) at 4,000 rpm, transferring power to the rear wheel through a 5-speed gearbox and chain final drive. With a specific output of 57.2 HP per liter and a 1,600 rpm working window between peak torque (4,000 rpm) and peak power (5,600 rpm), the engine character is prioritizing low-RPM tractability, mechanical longevity and relaxed throttle response over peak redline numbers.
On the scales, the Thunderbird TwinSpark measures 163 kg (359 lbs) wet (curb), translating to a power-to-weight ratio of 0.12 HP/kg (8.23 kg per horsepower). Rider ergonomics and chassis geometry center around a 760 mm (29.9 in) seat height — giving shorter riders and urban commuters confident flat-foot reach at traffic stops, combined with a 1,370 mm (53.9 in) wheelbase engineered for quick, flickable steering geometry. The 14.5-liter (3.8 US gal) fuel tank supports practical everyday commuting and weekend road stints, while factory top speed is listed at 120 km/h (75 mph).
Within MotoLibrary's Enfield archive, this model family spans 4 indexed model years from 2009 to 2012, allowing buyers to track year-over-year changes in emissions tuning, weight and equipment.
Specific Output
57.2 HP/L
Power-to-Weight
0.12 HP/kg (8.23 kg/HP)
Power Band Window
4,000–5,600 rpm
Standover Height
760 mm (29.9 in)
Engine
Displacement346.0 ccm (21.11 cubic inches)
Engine TypeSingle cylinder, four-stroke
Engine DetailsRoya Enfield Unit Construction Engine.
Power19.8 HP (14.5 kW)) @ 5600 RPM
Torque28.0 Nm (2.9 kgf-m or 20.7 ft.lbs) @ 4000 RPM
Compression7.3:1
Bore x Stroke70.0 x 90.0 mm (2.8 x 3.5 inches)
Fuel SystemCarburettor. BS29/UCAL
Fuel ControlOverhead Valves (OHV)
IgnitionDual spark
LubricationDry sump
CoolingAir
Transmission
Gearbox5-speed
Final DriveChain (final drive)
ClutchWet mulitiplate
Performance
Top Speed120.0 km/h (74.6 mph)
Chassis
Frame TypeSteel
Front SuspensionTele Scopic With Hydraulic Damping.
Front Travel130 mm (5.1 inches)
Rear SuspensionSwing arm With Gas Shock Absorbers.
Rear Travel80 mm (3.1 inches)
Wheelbase1370 mm (53.9 inches)
Ground Clearance135 mm (5.3 inches)
Wheels & Brakes
Front Tyre3.25-19
Rear Tyre110/90-18
Front BrakesSingle disc
Front Brake Ø280 mm (11.0 inches)
Rear BrakesExpanding brake (drum brake)
Rear Brake Ø152 mm (6.0 inches)
Dimensions & Weight
Dry Weight163.0 kg (359.4 pounds)
Weight incl.163.0 kg (359.4 pounds)
Power/Weight0.1215 HP/kg
Seat Height760 mm (29.9 inches) If adjustable, lowest setting.
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.
