Engineered by Yamaha for the allround motorcycle segment, the 2020 Yamaha YS125 features a 125 cc (7.6 cu in) liquid-cooled single cylinder, two-stroke configuration. 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 supports practical everyday commuting and weekend road stints.
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.
Specific Output
84 HP/L
Power-to-Weight
0.08 HP/kg (12.29 kg/HP)
Power Band Window
6,000–7,500 rpm
Standover Height
795 mm (31.3 in)
Engine
Displacement125.0 ccm (7.63 cubic inches)
Engine TypeSingle cylinder, two-stroke
Engine DetailsReed-valve-inducted
Power10.5 HP (7.6 kW)) @ 7500 RPM
Torque10.8 Nm (1.1 kgf-m or 8.0 ft.lbs) @ 6000 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.
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.
