At what psi can I travel 65-75mph?
This Maxxis pdf has the same table. Using the table(s) above, my ST175/80R13 with 1060lbs load could run at a minimum 35psi with ~4% reserve capacity. Is there a +10lbs rule? I run with +1...
Forum Discussion
Tires are tested in a laboratory on a rotating drum with a static force pushing down on the tire. It is not subject to pot holes or the crown in the road or other rough conditions which increased the load on tires. ST tires are tested to 65 mph and no more so who knows how much faster they can go. They might start flying apart at 66 or 86. One thing for sure, they will be damaged at sustained speeds higher than the rated speed. Increased speed causes increased heat and heat is the enemy of tires. If you need to go faster get LT tires.
