GY6 100CC 50MM QMB139 Big Bore Engine Kit with 64mm EGR PAIR Cylinder Head

Upgrade your scooter's performance with this comprehensive GY6 100CC 50MM QMB139 Big Bore Engine Kit. Designed for QMB139 4-stroke engines, this kit significantly increases displacement and power output, featuring a high-performance cylinder head with 64mm valves for enhanced airflow and combustion efficiency.

• 50mm Bore Diameter: Transforms your standard 50cc engine into a powerful 100cc unit, delivering substantial torque and top-end speed improvements.
• 64mm Valve Cylinder Head: Equipped with larger 64mm intake and exhaust valves, this head maximizes air-fuel mixture intake and exhaust gas expulsion for peak performance.
• EGR (Exhaust Gas Recirculation) PAIR Style: This specific cylinder head design is compatible with EGR systems and features a PAIR valve setup, ensuring emissions compliance while boosting power.
• Integrated Oil Pump Sprocket: Includes a 33-tooth oil pump sprocket to ensure proper lubrication for the increased engine demands of the big bore setup.
• Complete Variator Kit Included: Features a variator with a 62-tooth drive face and 8.5g roller weights, optimized to work with the big bore engine for improved acceleration and power transfer.

Compared to stock 50cc engines, this 100cc big bore kit offers a dramatic increase in power and responsiveness, making it ideal for riders seeking a noticeable performance upgrade. The 50mm bore and 64mm valve head are engineered for optimal combustion, outperforming standard upgrades by providing more torque and higher horsepower ceilings. This kit integrates essential components like the piston, cylinder, and head, ensuring a cohesive and powerful engine assembly.

Key Technical Advantages: Optimized Engine Power and Efficiency

This GY6 100CC Big Bore Engine Kit leverages advanced engineering to push the boundaries of your QMB139 engine's capabilities. The 50mm piston and cylinder bore, combined with the specially designed cylinder head featuring 64mm valves, create a formidable combination for increased displacement and superior airflow. The high-performance CDI and ignition coil ensure a strong spark for efficient combustion, while the included variator kit with 8.5g rollers is tuned to harness the extra power effectively. Expect a significant boost in acceleration, top speed, and overall engine performance that transforms your riding experience.