2002 Yamaha SR 400 Technical Analysis & Specification Breakdown
At the heart of the 2002 Yamaha SR 400 naked motorcycle, Yamaha pairs a 399 cc (24.4 cu in) air-cooled single cylinder, four-stroke architecture with road-focused gearing. In factory specification, peak output is rated at 27 HP (19.7 kW) at 7,000 rpm while maximum torque reaches 29 Nm (21.4 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 SR 400 measures 152 kg (335 lbs) dry, translating to a power-to-weight ratio of 0.18 HP/kg (5.63 kg per horsepower). Rider ergonomics and chassis geometry center around a 790 mm (31.1 in) seat height — offering a neutral standover height that accommodates most average-inseam riders without sacrificing cornering clearance, combined with a 1,410 mm (55.5 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 3 indexed model years from 2002 to 2014, allowing buyers to track year-over-year changes in emissions tuning, weight and equipment.
Specific Output
67.7 HP/L
Power-to-Weight
0.18 HP/kg (5.63 kg/HP)
Power Band Window
6,500–7,000 rpm
Standover Height
790 mm (31.1 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
Torque29.0 Nm (3.0 kgf-m or 21.4 ft.lbs) @ 6500 RPM
Compression8.5:1
Bore x Stroke87.0 x 67.2 mm (3.4 x 2.6 inches)
Valves/Cylinder2
Fuel SystemCarburettor
Fuel ControlSingle Overhead Cams (SOHC)
CoolingAir
Transmission
Gearbox5-speed
Final DriveChain (final drive)
Chassis
Wheelbase1410 mm (55.5 inches)
Ground Clearance140 mm (5.5 inches)
Wheels & Brakes
Front Tyre90/100-18 54S
Rear Tyre110/90-18 61S
Front BrakesSingle disc
Rear BrakesExpanding brake
Dimensions & Weight
Dry Weight152.0 kg (335.1 pounds)
Power/Weight0.1776 HP/kg
Seat Height790 mm (31.1 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.
Transmission
Transmission and final drive affect maintenance, smoothness and everyday usability.