General description AlwaysH Camshafts Replacement is designed for GY6 50cc, 60cc, 80cc, 100cc, 139QMB, and 139QMA engines, making it suitable for ATVs, 4 wheelers, quads, scooters, and mopeds. This camshaft is ideal for those looking to upgrade their cylinder and head for enhanced performance. Technical specifications Replacement for: GY6 50cc, 60cc, 80cc, 100cc, 139QMB, 139QMA engines Sprocket size: 34T Total length: 69mm (2.7 inches) Bearing diameter: 32mm (1.3 inches) Installation Easy to install with CNC machining for stable quality. Usage Recommended for use when upgrading the cylinder and head to achieve optimal performance. Other information Please check the model number and size before ordering to ensure compatibility.