Screw through the tyre tread but no deflation

[BMW_User]

I'm posting this here hoping that it's fine.

The other day I pulled off and immediately noticed some noise coming from the tires.
I've pulled over after 100 mt and found a screw that had punctured the tread of one tyre.
I've removed the screw as I have run flat tyres anyway and calculated that it must have penetrated roughly 12mm.

That tyre has 5-6mm left which means that the screw went through those 6mm + another 6mm deep probably.
Surprisingly, after one week I haven't seen the tyre losing pressure.

My question is:
How thick is the rubber underneath and how safe it would be to keep the tyre like this?
I'd like to try and repair it as I know that it has never run underinflated but a couple of garages said they are not allowed to repair run-flat tyres.

I'm going to have quite a long journey soon.
Any ideas or comments around safety and durability of the tyre with a puncture of 12mm depth and apparently no internal damage?

Thanks.

 

[bg1]

Just replace it. Why risk your life and / or others for £100!

 

[mmm-five]

The reason most places won't offer to repair a run-flat is they can't guarantee you haven't run on it flat (no matter what the owner claims). They'd be opening themselves up to all sorts of compensation/negligence claims if it was to go bang at high speed, so it's easier to say no.

A decent tyre place should be able to remove the tyre and check for any obvious damage to the internal casing - but it's probably not worth the effort to most, and they'd still simply tell you that you need a new one (for safety).

 

[mmm-five]

Just replace it. Why risk your life and / or others for £100!

You could however use the same argument to say that 7mm tread isn't as safe as 8mm in the rain, so why risk your life & other's, just spend £100 changing them every time you get below 7mm

A safe repair (i.e. done to the correct standard) is as good as the original tyre.

 

[M1k3yC]

I'd like to try and repair it as I know that it has never run underinflated but a couple of garages said they are not allowed to repair run-flat tyres.

Suggest you take it to ATS. Be honest about screw length, how many miles you've done, and so on. Ask them to check the tyre over and for advice. I don't think they will charge you for what is essentially a safety/tyre check. I am fairly confident that ATS will repair runflats but have strict criteria for doing so.

Disclaimer: I have no idea how safe the tyre is right now and am not qualified to speculate, but my personal opinion is that I would trust ATS to make that call based on experience at a couple of their branches and with the company as a whole.

 

[enuff_zed]

And if the screw didn't go right through, how would they repair it?
Thinking about it, how many times has a tyre got a screw in it like that, which has subsequently come out and we've been none the wiser.
Obviously now you know it makes sense to be cautious, but it is a run-flat so you could risk it?
Up to you, your conscience and the depth of your wallet really.

 

[Z4paul]

Hi, ive also got run flats at the moment and as a result of another thread i bought things called 'rats tails' ' you can find them on ebay and recommended by others... I think these should certainly get you out of an emergency situation but think others look at them as a longer term repair, depending of course on the damage/state of the tyre otherwise. Or, as above given your not stuck on a isolated b road be safe rather than sorry and replace

 

[road warrior]

here is the thing, your saying it didnt penetrate the casing, which is nice, BUT... you now have a weak point, where at one particular point you have a very small area of solid rubber, and maybe at some point in the future strain or impact will cause it to rupture and go bang. you have yet to discover the joys of driving on proper none RF tyres, ( this forum is rife with RF woes of tramlining and harsh rides) may i suggest you bite the bullet and get some proper tyres ? aside from the empty wallet you wont regret it.

and as enuff says, you cant repair it without impaling the tyre completely - ironic, and nobody will guarantee a RF repair for sure.

 

[BMW_User]

Thanks everyone for your responses.

To clarify, I drove 100 mt with the screw in and then I took it off using my keys.
The tyre (front) has almost 4 years and 5-6mm left.
The shoulder of the tyre has never run deflated as per above and the only 2 factors that made me think are:

1. The screw going 12mm inside (a bit too much for my liking) which to me is basically the end of the rubber and that might explain why it didn't go through further easily, because it reached the end point before the casing.
2. The tyre is already 4 years old, so it's old regardless and old tires have less grip anyway, so I could change both.

No problems with spending £230, I'm just pondering as this could happen any time anywhere and I wouldn't notice, so as someone has said above, if it's not damaged and it's not punctured, changing it for the sake of changing it doesn't sound necessary as run-flat tires give me this additional reassurance, that is, they would never allow me to run while deflated running the risk of disintegrating the tyre and lose grip.
I got tyre sensors.

 

[road warrior]

it sounds to me you had already decided, and simply wanted reassurance and didnt get it. The very idea of wanting to keep runflats ,even damaged ones is too wonderful to consider on a Z4. Knock yourself out :rofl:

 

[BMW_User]

If I knew the thickness of the tyre inside, I'd feel more reassured.
I am not worried about blowing the tyre, I know that it's not going to happen, but I don't want the hassle of having to replace the tires while abroad for a problem occurring as a consequence of this.

I'll go and hear some other experts near home and to see their viewpoint.

 

[Mr Tidy]

Depending where the damage is they can be repaired but you're more likely to find an independent tyre centre will do it, the national chains just want to sell tyres!

Back in 2013 I had a puncture in a Pirelli run-flat repaired and used it for over 10,000 miles with no issue.

If you are anywhere near Woking, Surrey try Martins Tyres in West End.

 

[enuff_zed]

Depending where the damage is they can be repaired but you're more likely to find an independent tyre centre will do it, the national chains just want to sell tyres!

Back in 2013 I had a puncture in a Pirelli run-flat repaired and used it for over 10,000 miles with no issue.

If you are anywhere near Woking, Surrey try Martins Tyres in West End.

But the issue still remains that, if the screw didn't go right through, you'd just be wedging a bit of rubber in the hole and it wouldn't really be held there, or actually form anything that acted as a repair would it?
I would have thought, to make a repair, they would first need to make the hole all the way through, so they could fit a proper plug?

 

[BMW_User]

As an update, after 10 days of using the car, the pressure is still the same, so I'd say that whatever the depth of the puncture in the rubber, this didn't affect the casing, hence I reckon there's no reason to intervene at the moment.
If and when I see an anomaly in the air pressure affecting that tyre, I'll replace it.