Positioned in Wk's scooter motorcycle lineup, the 2021 Wk SX 125 utilizes a 124 cc (7.6 cu in) air-cooled single cylinder, four-stroke layout. In factory specification, peak output is rated at 8.7 HP (6.4 kW) at 7,500 rpm while maximum torque reaches 9 Nm (6.6 lb-ft) at 5,900 rpm, transferring power to the rear wheel through a automatic gearbox and belt final drive. With a specific output of 70.2 HP per liter and a 1,600 rpm working window between peak torque (5,900 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 SX 125 measures 100 kg (220 lbs) dry, translating to a power-to-weight ratio of 0.09 HP/kg (11.49 kg per horsepower). Rider ergonomics and chassis geometry center around a 800 mm (31.5 in) seat height — offering a neutral standover height that accommodates most average-inseam riders without sacrificing cornering clearance. The 4.1-liter (1.1 US gal) fuel tank supports practical everyday commuting and weekend road stints.
Specific Output
70.2 HP/L
Power-to-Weight
0.09 HP/kg (11.49 kg/HP)
Power Band Window
5,900–7,500 rpm
Standover Height
800 mm (31.5 in)
Engine
Displacement124.0 ccm (7.57 cubic inches)
Engine TypeSingle cylinder, four-stroke
Power8.7 HP (6.4 kW)) @ 7500 RPM
Torque9.0 Nm (0.9 kgf-m or 6.6 ft.lbs) @ 5900 RPM
Bore x Stroke52.4 x 57.8 mm (2.1 x 2.3 inches)
Fuel SystemInjection
CoolingAir
Transmission
GearboxAutomatic
Final DriveBelt (final drive)
ClutchCVT
Performance
Emission DetailsEuro 5
Chassis
Frame TypeUnderbone
Front SuspensionHydraulic fork
Rear SuspensionDual shock
Wheels & Brakes
Front Tyre120/70-14
Rear Tyre120/70-14
Front BrakesSingle disc
Front Brake Ø220 mm (8.7 inches)
Rear BrakesSingle disc
Rear Brake Ø180 mm (7.1 inches)
Dimensions & Weight
Dry Weight100.0 kg (220.5 pounds)
Power/Weight0.0872 HP/kg
Seat Height800 mm (31.5 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.
Suspension
Suspension details can matter for comfort, road feel and long-distance riding.
Transmission
Transmission and final drive affect maintenance, smoothness and everyday usability.
