cruisingram, What year is the bike you have?
From what I read you have an 82 bike and some parts from a 77 bike.
The 80 up bikes use a TCI or Transistor Controlled Ignition. The TCI uses a set of pickups mounted on the stator. There is a magnet mounted in the rotor to trigger the pickups to signal the TCI when to fire the plugs.
The 70-79 bikes have no provision to mount the TCI pick ups. They also have a differnt wiring on the brushes. The 80 up have no grounded brushes, the 70-79 have a grounded brush. You can rewire the brushes to match your bike but it's better to stay with stock.
I would get an 80 up stator, that way you can easily use the TCI and it will plug straight up with no wiring mods.
jay760, the major difference in the early and late rotor are the magnet. other than that they look the same. If the way one mounts is different than the one on your bike it is not an XS650 rotor.
Leo