YS125

2021 Yamaha YS125 Technical Analysis & Specification Breakdown

Built around Yamaha's allround motorcycle platform, the 2021 Yamaha YS125 utilizes a 125 cc (7.6 cu in) air-cooled single cylinder, two-stroke layout. In factory specification, peak output is rated at 10.5 HP (7.6 kW) at 7,500 rpm while maximum torque reaches 10.8 Nm (8 lb-ft) at 6,000 rpm, transferring power to the rear wheel through a 6-speed gearbox and chain final drive. With a specific output of 84 HP per liter and a 1,500 rpm working window between peak torque (6,000 rpm) and peak power (7,500 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 YS125 measures 129 kg (284 lbs) wet (curb), translating to a power-to-weight ratio of 0.08 HP/kg (12.29 kg per horsepower). Rider ergonomics and chassis geometry center around a 795 mm (31.3 in) seat height — offering a neutral standover height that accommodates most average-inseam riders without sacrificing cornering clearance, combined with a 1,320 mm (52 in) wheelbase engineered for quick, flickable steering geometry. The 14-liter (3.7 US gal) fuel tank paired with a rated consumption of 2 L/100 km provides an estimated theoretical range of roughly 700 km (435 miles) between fill-ups.

Within MotoLibrary's Yamaha archive, this model family spans 4 indexed model years from 2018 to 2021, allowing buyers to track year-over-year changes in emissions tuning, weight and equipment.