Puncture Run flat.

[ALAW]

The yellow warning came on permanently on the display. Moved screen to the Tpms and sure enough driver side rear read 0.8. I usually run with 2.3. I first noticed the display going to work on the Thursday morning. On Friday i went to the tyre fitters on the Thursday night i pumped them up but by Friday morning they had lost a bit but the yellow warning had vanished. At the tyre fitters the pumped it up to 2.3 exactly and checked all the others they said see how you go come back if they go down. It did i took it back on the Monday this time they took the wheel off to reveal it had a puncture smack back in the middle of the tread. It was a small piece of a small dia drill bit. Anyhow it could be repaired and was at a cost of £34. So im happy with run flats they got me to work Sat ,Sun and Mon. I know a few of you dont like em and are opting to get normal tyres fitted. They bought me some time like they are supposed to do i dont think they are noisy but i know they are noisier than normal. Im happy with them and whats more the tyre was repaired. Im going to get this winter out of them and change the rears in spring and fronts in August. I will post on another thread what im going to put on, i think weve discussed what type of tyre. 

[LenT]

5 hours ago, ALAW said:

So im happy with run flats they got me to work Sat ,Sun and Mon. I know a few of you dont like em and are opting to get normal tyres fitted. They bought me some time like they are supposed to do i dont think they are noisy but i know they are noisier than normal. Im happy with them and whats more the tyre was repaired.

A very interesting account, Brent, and a good demonstration of how Run Flats and the TPMS combined to identify the slow leak and keep you mobile until it could be repaired.

As you say, these are trade-offs against the reportedly noisier and firmer ride of RFs.  It maybe that you were also fortunate that it was a rear tyre so the handling and steering were less affected than might have otherwise been the case.  Without the TPMS - and with the firmer sidewalls of the RFs - the loss of pressure might not have been so visibly obvious that it would alert you to the slow leak in the first place.

Occasionally I see accounts from Posters who find the warnings from the TPMS irritating and difficult to resolve and ask about disabling it.  I think your experience is a very good example of how that’s not such a good idea!

[ALAW]

17 hours ago, LenT said:

A very interesting account, Brent, and a good demonstration of how Run Flats and the TPMS combined to identify the slow leak and keep you mobile until it could be repaired.

As you say, these are trade-offs against the reportedly noisier and firmer ride of RFs.  It maybe that you were also fortunate that it was a rear tyre so the handling and steering were less affected than might have otherwise been the case.  Without the TPMS - and with the firmer sidewalls of the RFs - the loss of pressure might not have been so visibly obvious that it would alert you to the slow leak in the first place.

Occasionally I see accounts from Posters who find the warnings from the TPMS irritating and difficult to resolve and ask about disabling it.  I think your experience is a very good example of how that’s not such a good idea!

You make a good point there Len something that never crossed my mind. It would maybe have been different should it have been one of the front,s. 

[Don C]

For me, changing the tyres wasn’t because I dislike runflats, it’s because I need all season tyres for Peak District winters.  They’ve made the difference between me getting home or abandoning ship like so many others.  Of course, I’ve been lucky so far they haven’t completely blocked the road and I’ve got through.   

[Govanguy]

I thought run-flats couldn't be repaired?

I have a slow puncture dropping to 1.9 from 2.3 in a week. 

Funny thing though. I parked my car whilst on holiday for 2 weeks and returned to find the tyre still indicating 2.3 . 

The issue of the flat seems to have coincided with a drop in air temperature. I know cold air contracts.

[LenT]

 

21 minutes ago, Govanguy said:

I thought run-flats couldn't be repaired?

Correct!
If the tyre has deflated to the point where the wheel rim is running on the tyre wall, then the tyre cannot be repaired. 

Despite the tyre wall being reinforced, there is no way for a repairer to determine how much damage has been done and the chance of the tyre failing completely in further use.

The main point is that Run Flat is something of a misnomer.  It is only designed to enable a short, slow journey either to a safe situation or a tyre retailer.  

This article by Kwik-Fit gives a good explanation.

https://www.kwik-fit.com/blog/can-a-run-flat-tyre-be-repaired#

[Govanguy]

Went out to driveway this morning. 5c. Started car...drive down the street..yellow light comes on. 0.9 bar reading.... 

Car hadn't moved since my drive home from the airport on Sunday evening. 2.3 bar when I left car on Sunday.

[LenT]

4 hours ago, Govanguy said:

Went out to driveway this morning. 5c. Started car...drive down the street..yellow light comes on. 0.9 bar reading.... 

Car hadn't moved since my drive home from the airport on Sunday evening. 2.3 bar when I left car on Sunday.

Tyre pressure certainly drops with a decrease in temperature.  It can be enough to activate the TPMS warning light - I’ve had it myself.  But 5C is not that cold and 2.3 bar to 0.9 bar is surely a slow leak.

If you know what wheel it is, I’d examine the tread for a small nail - or similar - and the valve for an air leak.  Another possibility is wheel rim damage.

[johdhm]

Interesting point about run flats not being repairable if you drive with the tyre deflated.

I carry a small air compressor which works off the 12v power outlet - fits neatly under the boot floor.  This means I can reinflate a tyre if I get a TPMS warning.  This buys me a bit more time if I get a puncture, but obviously I still need to get to a tyre fitter quite soon to check it out.

[CplSam]

On 11/20/2023 at 10:56 AM, Govanguy said:

I thought run-flats couldn't be repaired?

I have a slow puncture dropping to 1.9 from 2.3 in a week. 

Funny thing though. I parked my car whilst on holiday for 2 weeks and returned to find the tyre still indicating 2.3 . 

The issue of the flat seems to have coincided with a drop in air temperature. I know cold air contracts.

"The issue of the flat seems to have coincided with a drop in air temperature. I know cold air contracts".

I have noticed this happening whenever we have a prolonged cold spell. My Runflats have to date never dropped below 2 Bar fortunately.

This winter will be the first time the car has been parked in a carport and not a Garage so I think I may see a bigger drop.

I am still a fan of both RF and the TPMS. I also carry a small air compressor, just in case.

Regards

[Govanguy]

This is  a strange one. I had the tyre, valve and seal checked over at my local tyre store. Nothing found.

Yesterday morning, -3c,  tpms comes on. Pressure dropped to 0.5 bar.

I inflated the tyre to 2.2 bar.

This morning, -5c.....tyre still 2.2...no air lost.

I`ve been running around all morning, no pressure drop.

I recently purchased a wireless inflator from AliExpress. No cables. Xiaomi is the manufacturer.Slightly bigger and fatter than a mobile phone. It inflates my "flat" in around 8 minutes and still retains 2/3 of the Battery power. Recharges  by USB C.

Impressive gadget.