I have had my race bike tampered with this season too - including the rear shock moved from one end of the scale to the other. The dial is very difficult to move, so it could not move itself. Unfortunately I don't know exactly when it was changed - we just found it last weekend but the bike had not been handling for a while. (I had been blaming myself, the Irish road circuits and my tyres in that order! ). I am glad the riders at the Manx picked the problem up sooner. For the record, I know other riders this has happened to, who are not at the Manx. There are clearly some pretty warped folk about - I could tell you a few names shock , but unfortunately it seems there are smiling assassins in the paddock too. Scary.