Keep losing tires

[Tireman9]

Originally Posted by thinder

Hey Tireman9,

What is the critical temp for these tires? I shoot them regularly with a laser thermometer when I'm pulling and I'm curious what temp leads to failure. I think the hottest I saw on my bias plys was 130F

Problem is that the IR guns only measure external surface temperature which has two problems.
1. The critical place on a Radial is at the belt edges and on a bias tire it is at the interface of the tread and body ply at the "shoulder" of thickest part of the tire.
2. The guns only report the surface temperature and since rubber is a poor conductor of heat the surface is always cooler than the internal structure

I have a couple posts on IR guns and their problems but in summary:

Guns don't measure the correct spot and the timing is very critical if trying to compare temperatures. When I was measuring tire temperatures with a needle probe at Indy I needed to collect temperatures at 12 locations on 4 tires in under a minute. If there was a problem that delays the last readings, they were considered "suspect".

[thinder]

Originally Posted by Tireman9

Problem is that the IR guns only measure external surface temperature which has two problems.
1. The critical place on a Radial is at the belt edges and on a bias tire it is at the interface of the tread and body ply at the "shoulder" of thickest part of the tire.
2. The guns only report the surface temperature and since rubber is a poor conductor of heat the surface is always cooler than the internal structure

I have a couple posts on IR guns and their problems but in summary:

Guns don't measure the correct spot and the timing is very critical if trying to compare temperatures. When I was measuring tire temperatures with a needle probe at Indy I needed to collect temperatures at 12 locations on 4 tires in under a minute. If there was a problem that delays the last readings, they were considered "suspect".

So there is no ballpark temp at all? Obviously 100F should be fine and 300F would be bad. I wouldn't think We're not talking Indy level margins here.

[cwf]

From Tireman9...
http://www.rvtiresafety.net/search/l...emperature?m=0

[thinder]

Originally Posted by cwf

From Tireman9...
http://www.rvtiresafety.net/search/l...emperature?m=0

Thanks for the link, I should have clarified my question. I'm not worried about any sort of over pressure due to increasing heat. I'm more curious if a tire alignment issue could generate enough heat to get to a temperature that degraded the structural integrity of the tire. Or even in the case of overspeeding a tire, if you could get a warning in sidewall temps.

[cwf]

Originally Posted by thinder

Thanks for the link, I should have clarified my question. I'm not worried about any sort of over pressure due to increasing heat. I'm more curious if a tire alignment issue could generate enough heat to get to a temperature that degraded the structural integrity of the tire. Or even in the case of overspeeding a tire, if you could get a warning in sidewall temps.

Anything that heats can/may generate overtenp. Each tire has design level for temp, flex cycles etc... Tireman explains

Cars tear up tires by alignment issues, suspension, poor driving habits....

[thinder]

Originally Posted by cwf

Anything that heats can/may generate overtenp. Each tire has design level for temp, flex cycles etc... Tireman explains



Cars tear up tires by alignment issues, suspension, poor driving habits....

Ok, so back to my question: do you know a temperature to look for? Do you know this over temp threshold?

[Boxster1971]

Originally Posted by thinder

Ok, so back to my question: do you know a temperature to look for? Do you know this over temp threshold?

From TST Tire Pressure Monitoring Systems web page FAQ:

"For your temperature setting, the default of 158° is safe for all tires. Tires typically fail between 170 – 200° F."

Source: https://tsttruck.com/faq/

This article from a tire trade publication has more details, but in same ballpark.
http://www.tirebusiness.com/article/...plate=printart

[cwf]

Originally Posted by thinder

Ok, so back to my question: do you know a temperature to look for? Do you know this over temp threshold?

Roger says.. "140-170 degrees"... or be concerned...

http://www.rvtiresafety.net/2011/06/...tures.html?m=1

For us... with external sensors, I set temp at 150 on our LT tires, 65PSI CIP. If OATis above 80. Going all the way to Big Bend, the TST sensors read as high as 135 range... OAT was 85 or so in the morning and over 100 by noon ... up to 105. Our air pressure and temps ran right where we expected.

For your the answer you want, it will be difficult... but, Roger's numbers are good for a start. Meanwhile, look up your manufacturer website for the info

[thinder]

I just spoke with Goodyear on the phone about the speed rating. I told them that people were saying there is a speed restriction Of 65mph on ALL trailer (st) tires despite speed ratings.

They went back, researched, verified and called me back several days later.

They said unequivocally the tires are designed to be run continuously at any speed at the speed rating and any speed below as long as pressures and load ratings were respected.

This, of course, is not an endorsement to do anything unsafe or illegal and road conditions always dictate speed.

But it does mean that pulling your trailer at 70 (with all other things set correctly) doesn't build up heat and cause a failure of a GYE.

[cwf]

Originally Posted by thinder

I just spoke with Goodyear on the phone about the speed rating. I told them that people were saying there is a speed restriction Of 65mph on ALL trailer (st) tires despite speed ratings.

They went back, researched, verified and called me back several days later.

They said unequivocally the tires are designed to be run continuously at any speed at the speed rating and any speed below as long as pressures and load ratings were respected.

This, of course, is not an endorsement to do anything unsafe or illegal and road conditions always dictate speed.

But it does mean that pulling your trailer at 70 (with all other things set correctly) doesn't build up heat and cause a failure of a GYE.

Great!! So ... back to your question... why are you "losing tires"? If you are confident the problem is not related to stated tire design... then either you ARE losing air, ARE beyond load design, ARE unfortunate enough to be picking up lots of road trash... or... someone is dragging your Airstream over curbs. Or, there is a problem with your suspension/ axles.

There are other possible issues, multiple issues, or one not yet identified.

BTW... the tire guys have no control over product use.

It is interesting that I have driven my whole life with 2 "flats", and one "blowout" due to rapid air loss caused by a rusty wheel.... until the last 4 years where I had 2 flats... both from "construction materials"..a screw and a 3/8" drill bit....

I have seen cars and trucks with bad "alignment" issues never have tire flats... only accelerated tire wear...

If none of this is helpful... well, hope you figure it out...

[Tireman9]

Originally Posted by cwf

Great!! So ... back to your question... why are you "losing tires"? If you are confident the problem is not related to stated tire design... then either you ARE losing air, ARE beyond load design, ARE unfortunate enough to be picking up lots of road trash... or... someone is dragging your Airstream over curbs. Or, there is a problem with your suspension/ axles.

There are other possible issues, multiple issues, or one not yet identified.

BTW... the tire guys have no control over product use.

It is interesting that I have driven my whole life with 2 "flats", and one "blowout" due to rapid air loss caused by a rusty wheel.... until the last 4 years where I had 2 flats... both from "construction materials"..a screw and a 3/8" drill bit....

I have seen cars and trucks with bad "alignment" issues never have tire flats... only accelerated tire wear...

If none of this is helpful... well, hope you figure it out...

Many cars only use about 50% of the tire load capacity as the size and inflation are set for parameters other than load capacity (mpg & handling response and stopping distance)