Join Date: Jun 2010
Location: Salt Lake City
Bikes: 2009 Windsor Wellington
Doh, I overlooked that you had provided your weight. So SB's recommendation for a 28mm-wide tire with roughly 100 pounds on each tire (the back tire will be supporting more weight than the front most of the time, so this is approximate) is 100 PSI. Since you're at 240 right now, this would be slightly higher. So you may want to look into buying 28mm tires that are rated to 110 PSI or so. I usually run my tires 20-30 pounds below SB's recommendation for comfort and have not had any problems so far, although 'snakebite' flats (pinch flats) will be more common if you run your tires low and ride on rough terrain or ride directly up onto curbs often (this type of flat is caused by the tube getting pinched between the rim and an external object).
So in my experience, you probably should be safe at 80 PSI, although you probably should check your pressures at least once a week as all tubes leak air over time. Note that many pumps will not be accurate if you simply put the pump head onto a partially-inflated tire and begin there; usually it is necessary to drain most of the air from the tire and then pump it up again from there to get an accurate reading.
Last edited by csimons; 08-04-10 at 10:34 PM.