i ground 1mm off my case saver today where chain was hitting it and am pleased to say that the mysterious noise i had whilst backing off is no longer there.peace of mind at last.
yeah the australian ones do most are removed by the dealer but not always another easy check/fix it's a washer welded into the end of the header pipe justhave to slip the muffler off and it's easy to see or ask the dealer if it was done .