I don't want to say too much but, you might be better off stopping your tear down at this point, packaging it up and sending this particular YS motor to Richard at Performance Specialties. It appears the ball bearing shield of the rear bearing in the above photo has disintegrated. I ran these motors for years and had similiar problems. Back then, I tried everything that was suggested. Based on your opening statement in this thread and the problems you and others have had, this is probably not a fluke! Thanks__Everette