Speed and blown tires
Another thought I had while driving home today again from our holiday camping trip up north. I posted about driving to fast and not surprisingly I was told I was going to fast at 68mph even though I ...
Forum Discussion
myredracer wrote:
Marathons are rated 65 mph but Goodyear says you can run them up to 75 mph if you add another 10 psi (not all Marathons though). I've never read about anyone actually doing that and if that's not a good idea or not. Does it mean that these tires are built stronger?
maxxis does similar and then adds another 10mph if you derate the load capacity by 10 percent.
the new goodyear endurance trailer tire has a N speed rating stamped on the tire. 87mph. and they advertize the N speed rating on the tire website.
Load index for the 225/75 15 LRE at 65mph is 117, 112 at 87mph 117/112N
so far goodyear endurance is the only one I've seen with a higher speed rating stamped on the tire. my older Maxxis did not.
Not that I'm going to tow over 65, but it means that goodyear had to do the testing for the N speed rating, and speed rating testing for other than ST 65mph rated tires is much more stringent and more detailed test procedure than the std ST 65mph test.
