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Radial tube in radial tire?

What are the consequences of putting a radial tube in a radial tire? Noticed today that I had a mesquite thorn sticking in my sidewall. Didn’t really look too big so pulled it out and air followed!! Tires are relatively new with only about 13k miles on them. A local tire business (the big one) wants $110 to replace the 205/65R15 Kumho Solus KR21 tire. Bought these tires from Treadepot last year and did not take the road hazard warranty. What are my options? Thanks for any helpful ideas. John

I think the best bet is just to replace the tire. A tube (provided you can find anyone willing to mount them, and you wheels will accomodate them) is not nearly as durable as the proper tire. Since your tire will have a hole in it, that presents a serious weak spot that could potentially fail further down the road.

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A Tube is so old school it is downright dumb. Sidewall damage usually requires a new tire, it is a safety issue, sidewall damage is the death knoll for a tire.

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I have to agree with FoDaddy. You’re better off to replace the tire itself. A cheap fix will just put you and others at risk of a blow out. If you do replace the one tire make sure you put the new tire on the back of the car, provided you have average wear on the current tires.

A tiny pinprick from a thorn and the tire becomes structurally unsound! Wow! How Fragile that tire is! Where does this type of thinking come from?
There are a couple of things you could do. You could put the thorn back in, and cut off the excess. You could use a tire sealant.
Yes, I know, you’ll hear, “Horrors, a tire sealant!” And, “The tire will explode at 70 mph!” The statements are founded on what? The most rational of thought? Or, are they, “I’ve always assumed…”

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You can use tubes in tubeless tires. I do that on a motorcycle with spoked wheels. However, I would never do this with a tire with a damaged sidewall. There is only one solution for sidewall damage, and that is to replace the tire.

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I wouldn’t think a mequite thorn would do too much damage to the sidewall but the trick may be finding someone to do anything about it.

Personally, I think it would be fine with a patch and a tube. Many years ago on a cross country motorcycle trip a rear tire blew on me during an embarassing and emotionally painful escapade and stuck between a rock and a hard place, I had to install a 185 X 15" radial car tube in a 5.00 X 16" Harley Davidson motorcycle tire.
In theory, this should have dumped me on my head within 10 miles. In practice, that tube carried me 900 miles home and stayed in there for 2 more years with no problems. (clean forgot about it.)

(As an addendum, sprinkling talcum powder inside the tire can help when a tube is used. The talc prevents tube chaffing.)

Holes are stress concentrators - and since the sidewall undegoes a very complex motion - so complex patches tend not to hold - the hole become the place where the crack will start. What you want to avoid is the sudden sidewall failure at high speed. Cracks will take a while to develop, but they eventually will fail the tire. So it’s best to replace the tire.

If you want to know more about stress concentrators or crack propagation, Wikipedia does an OK job of explaining them.

Go to some place that does heavy truck tires. Ask them if they will do a “section repair” for you. It is done all the time. Although a section repair is still going to cost you about 40 bucks.

Too bad it was in the sidewall. They flex too much for a plug to hold. But for only a few bucks risk it’s worth trying one.

If it doesn’t work, replace the tire. Don not use Slime or and other goo, as they’ll squirt out the valve when you adjust the pressure and gum it up, and they leave so much mess that lots of shops won’t work on wheels with that stuff in them.

I doubt that anyone anywhere will not recommend against the use of a tube. It’ll change the tire’s handling and performance characteristics to where it may be unsafe.

A tiny prick is a major stress point which can lead to catastrophic tire rupture!?
Is that because a rubber tire is so brittle?
But, it’s ok to have a have a small nail puncture in the tread area, ream it out with a 1/4 inch reamer, and force a larger plug into it? Structurally, that large hole is benign for the tire because it was make intentionally with a tool?

Yes, I’m aware that the ARA(?) American Rubber Association advocates tire plugs.

CapriRacer, I’d be glad to read your article on stress concentrators if you would give a more specific reference than, “in Wikipedia”.

I would patch the inside of the tire with a basic tire patch kit and then go with a tube. Follow OK’s advice and shake in some talc powder . . . the constant rubbing of the tire against the tube could create heat . . . and the talcum powder will dial this down a bit. Used to use this procedure in dirt track racing, never once had an issue with it. I can’t imagine how a thorn would make a hole bigger than a nail hole. Keep an eye on it and move on. Rocketman

Thanks everyone who replied to my question. Took the tire down this morning to a smaller tire shop that had Kumho tires–Rick took one look at where the thorn went in and declared: patch that tire!! Evidently was not far enough down the sidewall to cause any problem. Drove away 15 minutes later a happy guy. I highly recommend O’Malley’s Tire Sales on the east side of San Antonio. Thanks all again. John

Ah … well … ah… I typed in the words “stress concentration” in the Wikipedia search box and it took me right to the article. I did the same for “Crack Propagation” - and that took me to “Fracture Mechanics”. I don’t understand what the problem is.

Here goes again. I just wrote a lengthy explanation as to why you don’t patch sidewall but when I hit submit, I got a DNS lookup error and all is lost.

In the days of bias ply tires, you could patch the sidewall and get away with it. That is because the strength in the sidewall was omnidirectional. In radial tires, most of the strength is unidirectional. A small break in the sidewall weakens the already weak longitudinal direction. Its like a wood board, it breaks easier with the grain as opposed to against it.

Since your thorn was close to the tread, the sidewall still benefited from the proximity of the belts. If the thorn had been further up the sidewall, the repair would not hold and the tire would fail. It would be dangerous to drive but I think you lucked out this time.

I case someone is reading this. The use of tubes in motorcycle tires is accepted practice, but NOT passenger car tires.

I agree with @FoDaddy, just replace the tire.

Since that tire is now over 11 years old, it has probably been replaced by now.

Would be interesting if @jabjtom could let us know how the tire held up after the patch.

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I’m pretty sure the Ford/Edison Museum in Fort Myers is still using tubes in the tires when they drive Edison’s Model A and Model T Fords for parade duty.

When a tube is used a puncture usually results in a blowout while a tubeless tire usually deflates slow enough that the driver reduces speed and avoids a catastrophe. And a tube in a tubeless tire invites a blowout. A flap is needed to protect the tube from chafing on the wheel and talcum powder is needed to allow the tube to slip onto a proper fit and withstand normal flexing. And the tube should be partially inflated then deflated repeatedly. Tube chafing is a significant cause of blowouts on tires using tubes. It is a mistake to think that using a tube in a tubeless tire results in a more reliable, puncture proof tire.

Zero tolerance for sidewall repair seems like overkill though.