Tire Problems or Operator Problems? (1 Viewer)

[beveldrive]

We've been tackling the NMBDR in sections as weekends allow. This past weekend was to be final completion by finishing the Jornada del Muerto and Gila areas. Unfortunately, we continue to have tire issues and I'd be interested in thoughts regarding what we are doing wrong. We started the NMBDR with new Cooper Discoverer AT3 4S tires. On a particularly rocky (but relatively fast 20 mph) section we had two rear tires fail within a couple hours. We did not air down for that section and while I don't recall the exact pressure we were running, it was probably in the 33-34 PSI range. We had to limp into Carlsbad where we purchase 5 BFG K02s in the best size they had (265/70R18 E load). We inflate these to 40-42 PSI. On the next NMBDR section we had a puncture from a screw (also not aired down due to 20+ mph speeds). Fast forward to this past weekend where we got no more than 2 miles into the final section where we suffered a puncture from a key (weird). We were not aired down on this section and were inflated to 42 PSI cold. My guess is that the Coopers were not up to the task and that we should have aired down slightly and kept speeds lower. I am surprised by the punctures in the KO2s however. Did we just get unlucky? I don't think these tires should be particularly puncture prone at one pressure vs the other in the 30-50 PSI range. Thoughts?

 

[Madtiger]

Tread punctures are unavoidable and unlucky. Most off-road LT tires are more about preventing sidewall punctures. Nails, keys, etc can all go thru rubber (even if they have steel plies or nylon reinforcement).

 

[rscoleman]

Bad luck but great story for future.

 

[Sandroad]

Unlucky on the punctures (though I agree the key is weird), but I’m sure others on the forum would be interested in exactly what happened to the Coopers.

 

[TheIcemanCometh]

I think the trail is try to tell you something. As said, such punctures are just bad luck. Tires are not impenetrable. I am quite amazed at what and how they can be damaged. In some way not unlike rock chips.

 

[tbisaacs]

If you are going too fast to air down and keeping having punctures—slow down and air down is the obvious answer.

 

[TeCKis300]

As I read the first post, I was thinking about exactly the video @tbisaacs posted.

It's critical to airdown.

20 mph+ speeds is not a concern to airing down. A general good go to pressure is ~18 PSI for most everything. I'll do spurts of 60+ mph at that pressure. Silty hot sand is about the only time I'll reach for low teens as that's a different animal all together.

I'll say the 265s on a stock 8" wide wheel is not a great size as that's going to impact bead retention if you like to impersonate a rally driver with harder turns. 20PSI is probably good for your setup.

There's so many other pros to air down and very little downsides. It's protects the trail, easier on the driver, easier on the rest of the car with much less transmitted NVH, and most importantly protects from punctures.

 

[grinchy]

Super bad luck! Concur that airing down 'always' is the way to go. Of course, this is assuming you've got a good way to air down and back up that isn't too inconvenient.

 

[bloc]

 

[gaijin]

FYI, here's a link to the Drivers Guide referenced in the video:

4WD Drivers Guide

HTH

 

[beveldrive]

Guys, thanks for all the feedback. We will air down on our next outing and keep speeds in check. It's not like we were out rallying, but there is always room to go a bit slower.

WRT the question about the Cooper AT3 4S tires we were running earlier: I loved those tires for their road manners and forest road grip. We were running in the Lincoln Forest portion of the NMBDR, well south of Weed NM. The terrain is very rocky, but not technical at all. Our speeds were in the 20-25mph range and over the course of 4 hours we had two rear tire failures. The tires both developed leaks in the tread with no obvious foreign material left in the tire. The leaks were small, like a single tiny crack in each tire. I tried plugging the tires and both punctures continued to open up. It was like the supporting structure inside the tires failed and the holes blew out. We focused on the better of the two tires and used a ton of plugs to nurse it into Carlsbad. We pretty much had to stop every few miles to top off or replace plugs. Both tires ultimately looked like they exploded from the inside out.

 

[grinchy]

Guys, thanks for all the feedback. We will air down on our next outing and keep speeds in check. It's not like we were out rallying, but there is always room to go a bit slower.

WRT the question about the Cooper AT3 4S tires we were running earlier: I loved those tires for their road manners and forest road grip. We were running in the Lincoln Forest portion of the NMBDR, well south of Weed NM. The terrain is very rocky, but not technical at all. Our speeds were in the 20-25mph range and over the course of 4 hours we had two rear tire failures. The tires both developed leaks in the tread with no obvious foreign material left in the tire. The leaks were small, like a single tiny crack in each tire. I tried plugging the tires and both punctures continued to open up. It was like the supporting structure inside the tires failed and the holes blew out. We focused on the better of the two tires and used a ton of plugs to nurse it into Carlsbad. We pretty much had to stop every few miles to top off or replace plugs. Both tires ultimately looked like they exploded from the inside out.

That sounds like overheating.