Thanks Paul, I bought a pattern set of GS 800 mirrors for my GS 1200 which they say are 10m, but there ever so slightly out that when I try to screw them in they start to cross thread also the locking nut looks the right size but it won't thread into the mirror for some reason any thoughts? Any way of getting them on? Someone mentioned a thread adaptor nut I haven't got a clue what that is any help appreciated.