OK then, youre happy with the bearings, there's no play. I'm happy with the seating of the rotor taper, it comes off with a bang. All you can do then is
1: give all the magnets a wiggle, they're all tight arent they?
2: Dress the iron core of any coil at the point where the tipex is rubbed off, use a file to just remove a little of the material, you can see the evidence, it has left a burr on the edge of the core hasnt it....Just dress it a little at that area....proper fettling