Originally Posted by melissab
Was that a trailer tire rated at 65 mph? I've wondered what would happen on the rare occasion I needed to exceed 65 to get through a hairy traffic situation how long it would be safe to travel at say 70 before risking such a blow out.
There are so many variables that speed rating is too simplistic to take the blame alone. Even this long winded post is not comprehensive.
First...Let me throw the obligatory bone here and say that you should restrict your speed to 65 or lower under all conditions.
Tires have their worst speed capability when brand new, at high speeds, and on hot pavement.
The reason for this is that heat build up is the primary enemy.
New tread holds more heat, high speed retains more heat, and of course hot pavement conducts more heat into the tire.
A tire on dry pavement runs cooler at half tread.
A tire at full inflation runs cooler.
A tire on cool pavement runs cooler.
Even a well balanced tire runs cooler.
And of course a tire runs cooler at lower speeds.
There are other factors such as tread design and depth,carcass design, tire material, load, attitude and tongue weight
,and yes the aging of the tire itself.
Still there are no magic numbers or magic formulas to guarantee that you will never have a catastrophic tire failure. Everything else being perfect there are always road hazards.
I say all of this just to come to one point...
Don't worry but carry a spare!