Hence my comment about road camber in post 3, thought Mike O seemed to disagree, done enough road trips abroad to notice tyre wear on the other side, as I said before, road camber, simples.My brother took a Diversion 600 into the Alps. Exactly the same. Back in UK at tyre change MOT time the mech was stunned to see so much shoulder tread wear with relatively little central wear. It was worn more on the left.
My GS (used in UK) wears RHS shoulder before LHS.
Road cambers have got to make a difference. I regularly make a LH T junction turn- often there is no traffic so I swing out and crank the bike over often just touching left boot down. The camber is very much to the left. I still have a wider chicken strip in left than on right.