Hoca QMB139 4T Power Pack, Part #169-233

Hoca 4T Racing Kit for 50cc 4-stroke QMB139 Scooters and Engines. This kit includes everything you need to increase overall speed, horsepower and torque. You may need to modify your engine case to accommodate the larger cylinder. for Cylinder Heads with 64mm Valves (Short Valve Style) Includes High Performance CVK 26mm HP Carburetor. Performance Transmission Kit. Power Intake. High-Angle Camshaft. 1500 RPM Torque Yellow Drive Spring. Big Bore Kit (50mm). Complete Performance Cylinder Head. Overall Height (cylinder): 71mm. Valve Overall Length: 62.3mm (compatible with 64mm Short Valve Style Heads).