Can one fix a runflat flat?

tires
mini
cooper

#1

Hi everyone,



My fiancee and I have a new(er) Mini Cooper S with about 5K total miles on it. We bought the car with run flat tires, and passed on the tire insurance. We’re a bit worried about that fact now, as we just had our first flat. It’s a nail in the tire (between the treads in the center of the tire - no sidewall), and it’s causing a very slow leak.



From what I’ve read, you can’t plug a run-flat tire. You have to replace the whole tire when this happens. Which seems flat-out absurd. I’m really hoping folks here can tell me this is not the case.


#2

Sorry that is the way it is. I am not a fan of those tyres, especially today with cell phones so you can get someone to help you out.


#3

Sux, don’t it? Hardly worth the convenience of getting where your going without stopping. Instead get AAA and call them when you get a flat if you hate changing tires on the road (which is pretty unsafe on highways especially).
Replace them with a good 60,000 mile-plus tire when your current set wears out or are punctured. I recommend Michelin tires because they stop, wear and corner as well or better than any tire on the market, and are well worth the cost. Especially if you can find them on sale.
Try to replace two at once, front or back, at least, as you can afford it.


#4

IIRC, the reason why the Mini has runflats is that there’s no room for a spare. So unless you want a spare tire occupying some of the Mini’s scant interior space or want to get a tow every time you get a flat, you have to stick with the runflats.

I suppose another solution might be a can of fix a flat, but the tire shops will hate you.


#5

I recently heard an explanation of this situation that seems plausible, but I’m definitely curious if others agree. Supposedly, if you don’t drive on the tire when it’s flat, then it can be repaired like any other tire. The issue is one of liability, because the tire shop has to take your word that you stopped right away and didn’t use up the limited mileage for driving on the tire when it’s flat. If a customer lies and the tire later disintegrates, unfortunately the tire shop is likely to be sued.


#6

Lion,

As a tire engineer, perhaps I can embellish the explanation enough so that it is coherent.

RunFlat tires work because there is a stiff insert in the sidewall. It provides vertical stiffness much like the inflation pressure does in normal tires.

When normal tires are operated deflated, the sidewalls can contact the pavement and there will be wear marks. indicating the tire is damaged internally (meaning beneath the visible rubber layers, not meaning the inside air chamber!) The sidewalls can also buckle and be damaged that way. In either event, there is evidence that there may be a problem. While tire shops have been known to repair such tires, they are just being foolishly risky - and with someone else’s life!

But with RunFlat tires, there can be structural damage without the evidence of it - because the damage is between the insert and the rest of the tire. For this reason, repairs on RunFlat tires carry a hugely greater risk of failure - and hence the warning from the manufacturers and the reluctance of tire shops.


#7

If you read the original post…slow leak which means the tire didn’t “run flat”…can’t those be plugged since no sidewall damaged occurred?


#8

There are 3 possibilities:

  1. The guy who is going to repair a tire, does so without asking questions - he just does it. He doesn’t inspect the tire, he just proceeds without any thought to whether or not it is truly repairable - and without any thought to the risk involved to both him and his customer. This is likely the most common situation. Needless to say, this is not a good situation and sometimes leads to some tragic consequences.

  2. The guy who is going to repair a tire asks questions to see if the tire was operated in a way that would damage a tire to the point where the risk of failure is too high. He also inspects the tire to see if there is damage. He then makes a decision to do the repair or not. The question here revolves around how much does he know and understand about how tires work - and in this case, specifically how RunFlat tires work. This is a pretty complex situation and it would be understandable if he chose not to do the repair, considering the legal liability he is taking on if the tire subsequently fails.

  3. The guy who is going to repair a tire does the repair at the insistence of the customer. The guy even has the customer sign a waiver. I’m not an attorney, but my understanding is that a person can not sign away his rights - and since the guy doing the repair is very likely to be more knowledgeable than the customer, the courts would view the guy doing the repair as having the responsibility for any subsequent situations.

So while technically the OP poses a situation where one could repair a RunFlat tire - and it would likely be OK - the legal situation is such that it is understandable that the repair would be refused.

And I’m not going to go into the problems with doing plugs as opposed to a plug/patch.


#9

Hello everyone, thanks for all the comments. Very informative. We did found a tire shop that says they can repair the leak; apparently, they take it off and repair it from the inside - no plug.

CapriRacer, I’m not sure which of your three scenarios we’re operating under, but we do know that the tire was flat for a short period of time we were using it (sorry, mshugna - I wasn’t explicit enough). We had thought the flat tire sensor was misbehaving at first, since after it went off, we could detect no pressure loss by gauge measurement. It knew better than we did, apparently.

The time period when the tire could have been flat would have been in-town driving (so not high-speed), but if it’s not even possible to estimate the damage even after taking the tire off, perhaps we’re better off replacing the tire this time around. It’s good to know that fixing them is possible though, if care is taken after the initial pressure loss occurs. Just need to have more faith in the equipment when it complains.


#10

Mshugna / Aronbeat,

This is exactly the situation that lawyers just salivate over.

So I hope everyone understands why someone might not repair a RunFlat tire in order to avoid such situations.