I recommend Continental Grand Prix 4 Seasons in the 28 mm size. I have about 1000 miles on a set of them and have yet to have a flat. Maximum pressure is 115 psi so you can pump them up if you want. Recommended pressure is 80 psi. My experience is that you can run 90 psi on chip base roads and laugh at your skinny tired buddies on their 23's.
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