[Fordie]

Glyn, I think you may get more lean angle (not that you need it)because the 180 is a bigger profile tyre its like sitting on a tennis ball compared to a football. The front strips would then decrease. You may also feel the bike a little harder to turn in and don't forget the weight factor as the 170 is lighter than the 180 but by how much I don't now .Regards 4D