Originally Posted by
RubeRad
Always ride the widest, lowest-pressure,
most supple tires you can. That last one might be the most significant factor (but also drives up price)
CyclingTips Podcast, Episode 9: Rethinking road bike tire sizes and pressures | CyclingTips
My Surly CrossCheck is wearing Schwalbe Hurricanes; not terribly supple perhaps (they're no Marathon Supremes), but 700x50 in the back and 700x42 in the front. I check the pressure every day by riding over the steel triangular bar that the parking lot gate at work rolls on. When they get too low, I find they're down around 15-20psi, so I air them 'up' to 30.
+1!
I commute on 29x3.0" Vee Rubber Tee Fattys aired "UP" to 9.5 PSI in the front and 10.75 PSI in the rear. Not good for standing up and srpinting but awesome for everything else, including hi-speed cornering in bike lanes where gravel, broken glass, and other debris are common.
If I hit a trail on the weekend I can go as low as 6-7 PSI in the front but only on trails, at that pressure, there's SO MUCH traction on pavement the 'self steer' which these tires are known for is pronounced.