A replacement Rotor for GY6 4 stroke engine, Weak magnetization can cause faulty running, and damaged rotors can cause severe engine damage and noise.
Mechanics Note : 8 pole stator/rotor will work on any GY6 50cc 139QMB (and many others like 2-strokes) as long as you have a matching 8 pole flywheel rotor to go with it and have 4/5 wires. When you order a stator generator, be sure it matches the number of poles your rotor was made for. And in reverse, if you order a flywheel rotor, be sure it matches the number of poles on your stator. If you need both, order a matching 8 pole stator generator and flywheel rotor.