I'd go with even bigger tires. Grant Petersen at Rivendell has written a lot about tire selection, and i think he recommends 35s at 75psi for 200-pound riders. sounds soft and slow, but he convinced me when I bought my atlantis. I've been using 35mm Panaracer paselas for three or four years, and I'm never going back.
If you don't want to go that fat, i still think you'll get considerable relief with, say, 28 or 32mm tires with less air.


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