Originally Posted by
swc7916
Since we are used to the 1.25 width, I would be reluctant to make too big of a jump in width and would probably go with the 1.5. My only reservation is the tire pressure - I always run at 100 psi and I don't how much a lower pressure would affect the performance.
Lower pressure had been a concern of mine in the past, but I've worked through it
Jan Heine suggested starting at about 70psi and adjusting. That doesn't sound like enough, but I've come to the conclusion that I can get by with less air than I think I need, especially in a wider tire. On my single bikes I have experimented and found that 80-85 psi in my 700x25 Vittoria Corsa Evos yields a much nicer ride with no performance penalty that I can notice. I've also settled in at about 70 psi with 700x27 Pavés and 50 psi with 700x35 Clement X'Plors. FWIW, I have ridden the Clements @ 50 psi on some pretty serious technical descent and felt entirely comfortable. They are on a gravel/cross bike.
With that settled in my mind, I still can't decide whether I want the 1.5 or 1.75 ......