Positioned in Yamaha's allround motorcycle lineup, the 2011 Yamaha SR400 features a 399 cc (24.4 cu in) air-cooled single cylinder, four-stroke configuration. In factory specification, peak output is rated at 27 HP (19.7 kW) at 7,000 rpm while maximum torque reaches 62 Nm (45.7 lb-ft) at 6,500 rpm, transferring power to the rear wheel through a 5-speed gearbox and chain final drive. With a specific output of 67.7 HP per liter and a 500 rpm working window between peak torque (6,500 rpm) and peak power (7,000 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 SR400 measures 131 kg (289 lbs) dry, translating to a power-to-weight ratio of 0.21 HP/kg (4.85 kg per horsepower). Rider ergonomics and chassis geometry center around a 810 mm (31.9 in) seat height — offering a neutral standover height that accommodates most average-inseam riders without sacrificing cornering clearance, combined with a 1,405 mm (55.3 in) wheelbase engineered for quick, flickable steering geometry. The 12-liter (3.2 US gal) fuel tank supports practical everyday commuting and weekend road stints.
Within MotoLibrary's Yamaha archive, this model family spans 6 indexed model years from 2011 to 2019, allowing buyers to track year-over-year changes in emissions tuning, weight and equipment.
Specific Output
67.7 HP/L
Power-to-Weight
0.21 HP/kg (4.85 kg/HP)
Power Band Window
6,500–7,000 rpm
Standover Height
810 mm (31.9 in)
Engine
Displacement399.0 ccm (24.35 cubic inches)
Engine TypeSingle cylinder, four-stroke
Engine DetailsSingle cylinder, four-stroke
Power27.0 HP (19.7 kW)) @ 7000 RPM
Torque62.0 Nm (6.3 kgf-m or 45.7 ft.lbs) @ 6500 RPM
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.
