This is the H-D charging system kit. At the top left is the voltage regulator, below that is the stator assembly, and on the bottom right is the rotor cover. See All 5 Photos Here's the sprocket-shaft ...
You can find stators in many types of electric generators, motors, and rotors. A stator is also the part of the alternator that’s stationary (while the rotor, also called the flywheel, moves).