## 80cc Cylinder Head - More Power for Your 139QMB/QMA (GY6 50) 4T Scooter This complete 47.00mm 80cc cylinder head without EGR with enlarged valves is the perfect solution for anyone who wants to increase the power and performance of their 139QMB/QMA (GY6 50) 4T scooter. ### Increased Engine Performance The enlarged intake (62mm) and exhaust (61mm) valves provide better airflow, resulting in a noticeable increase in power and torque. The lack of EGR further contributes to improved performance by eliminating exhaust gas recirculation. The combustion chamber diameter of 46.5mm has been precisely selected for optimal operation with the 80cc cylinder. ### Easy Installation and High Quality The cylinder head is designed for easy installation in 139QMB/QMA engines. The mounting bolt spacing of 50x50 mm and the diagonal of 71 mm ensure compatibility with popular scooter models. High-quality workmanship guarantees long life and trouble-free operation. ### Technical Specifications: * **Capacity:** 80cm³ * **Piston Diameter:** 47.00mm * **Intake Valve:** 62 mm (head diameter), 23 mm (plate diameter), 5 mm (stem diameter) * **Exhaust Valve:** 61 mm (head diameter), 20 mm (plate diameter), 5 mm (stem diameter) * **Combustion Chamber:** 46.5 mm * **Mounting Bolt Spacing:** 50x50 mm * **Mounting Bolt Diagonal:** 71 mm * **No EGR** Detailed dimensions are shown in the picture.