errr... my sprocket hub. :lol: I'm getting contact between the sprocket and the swingarm eccentric. A Ducati mechanic at the local dealer diagnosed that the inner surface was worn out. Presumably by running with the sprocket assembly at the wrong torque and or having it loosen up. I don't know, still scratching my head on this one. It must be the pn. that I listed as the part changed along the dev. of the series.