Review on Trkimal 100cc Big Bore Kit for 64mm Valve - 139QMB Moped Scooter Engine - 50mm Bore Upgrade Set with GY6 Cylinder Rebuild Kits, 6pin Racing CDI Ignition Coil, Performance Spark Plug, and Clutch Spring by Kev Mills

I have worked with many engines but never with a scooter. I couldn't believe everything in this set for the price. Less than four hours passed between loosening the first screw and starting the engine at a leisurely pace. The scooter works great now. Torque and power are higher than I expected. Works smoothly. And he started right away. Now I just need a new starter because the compression is so high and it's good! The old starter works but could be better. Update: still works great!