Upgrade your pit or mini dirt bike with this 140cc 4-stroke single-cylinder engine, designed for riders seeking reliable performance, smooth gear shifting, and versatile starting options.
The engine produces 7KW of power at 8500RPM and 9.5N·m torque at 5500RPM, ensuring strong acceleration, climbing ability, and consistent off-road performance.
Featuring a manual wet clutch with 4-speed gearbox (01234), the motor provides smooth and precise gear transitions, while electric and kick start options ensure easy starting in any situation.
The complete installation kit includes kick starter lever, gear shift lever, manifold set, engine cover, wiring harness, carburetor, air filter, clutch lever & cable, twist throttle with cable, and exhaust pipe with muffler, making it convenient to replace or upgrade your dirt bike engine.
Compatible with a wide range of mini and pit bike models: CRF50, CRF70, XR50, XR70, Z50, Z50R, CT70 Mini Trail, Z50 Minitrail, Monkey Bikes, XL70, SSR 110, RFZ 125, TaoTao DB14/DB17.

Engine Type: Single Cylinder, Horizontal, 4-Stroke, Air-Cooled
Displacement: 140cc
Bore × Stroke: 56mm × 57mm
Max Power: 7KW @ 8500RPM
Max Torque: 9.5N·m @ 5500RPM
Idle Speed: 1500±150 RPM
Compression Ratio: 8.8:1
Start Mode: Electric Start (Lower Position) + Kick Start
Clutch Type: Manual Wet Clutch
Transmission: 4-Speed 01234
Front Sprocket: 15T, 428 Chain, 17mm Shaft
Valve Clearance: 0.05±0.02mm
Primary Ratio: 3.722
Transmission Ratio: 3.822
Gear Ratios: 1st: 3.272, 2nd: 1.937, 3rd: 1.350, 4th: 1.043
Engine Oil Capacity: 900ml (15W/40W-SE, 4-Stroke)
Dimensions: 470 × 275 × 280mm
Weight: 23kg