SR 400

2012 Yamaha SR 400 Technical Analysis & Specification Breakdown

Positioned in Yamaha's allround motorcycle lineup, the 2012 Yamaha SR 400 relies on a 399 cc (24.4 cu in) air-cooled single cylinder, four-stroke powerplant. 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.