under power the top is pulled as tight as hell which lets the bottom section that you were rattling get even slacker,try and wrangle a mirror up there to spot the area it might be rubbing on,go to the dentist and have some teeth pulled out or drilled and gansta gold teeth fitted(i like solid chrome myself) then when hes not looking steal the little mirror they use,,,i think that chain looks past its use by date,,i know its a major job but you want to just ride the bike and not have any issues once its on the road,,you have a spare engine see how you go taking it apart?every single piece has to be washed and cleaned almost germ free before reassembly,,its a sort of plan A becomes plan B thing so while its apart the cam chain should be done,replace any sloppy bearings,look at the dogs on the gears and forks etc,each and every seal replaced,you can get away with reusing bearings etc if they are good,,the primary chain is a case wrecker if its let go too long.
