Now as I understand it, this ain't strickly the done thing, but a fair fiew of you do it.
Was wondering how folks had found them. Any significant diadvantages or advantages.
Please note I'm not interested in make and model opinions but your honest opinion of fitting both sizes.
I pressume a 180 / 55 on a 170 rim would be pinched in, increasing its profile height pushing its aspect ratio up towards 60,( the standard on a 170) and giving it a degree or so more lean before reaching the edge. From my experience with conti ra2's there comparatily high profile gives them a very lively quick to turn feel, but increases centre wear (also helped by soft centre).
Probably gonna put a set of bridgestone s20 which do 170's but dunny sportsmart, the other top contender only do 180's.
Any help from actual testing much appreciated