*When I suspected something was wrong* Was when I had the motor outside the vehicle, and was running it free.
It sounded like there was a bad bearing inside. And felt like alot of vibration untill I reached WOT. I didn't think that was right so I disassembled it, and checked the bearings. It was clean, and it seemed like it was alright. Instead of putting the stock rotor back in, I replaced it with the novak 3.5 upgrade. Immediately after install the smoothness came back to the motor, and just ran plan better!! So I figured that the rotor was bad after that. I don't think it "Came apart though" ? I'm not sure.