I use the 170/60 ST1300 rears all the time with no problems (instead of the 160/70 stock). If you have a 96 or later ABSII, the fronts are actually the same size as the ST1300s front - 120. I have heard of folks running the 120 width on the 110 front rim, but I've never tried it. I do know that an ABSII front rim will work on a standard front with the 120 tire and no clearance problems (I do that on my 97 standard).