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MG parts spares and accessories are available for MG T Series (TA, MG TB, MG TC, MG TD, MG TF), Magnette, MGA, Twin cam, MGB, MGBGT, MGC, MGC GT, MG Midget, Sprite and other MG models from British car spares company LBCarCo.

MG MGA - Rubber advice!

Hi all you rubber experts out there. Just noticed a set of wheels for my roadster have 16 year old Pirelli P6000 tyres fitted. I know all the "experts" say replace if over 7 year old but on what grounds? These tyres don't have any visible cracks and don't feel that hard compared to newer tyres using the finger nail test. Also they have been kept inside in the dark mostly, except for when used on a few runs. What durometer reading is considered too hard for road use? Is there any criteria other than hardness that determines their usabililty? I doesn't appear that belting degradation or ply separation has occurred looking at them.
Mike
Mike Ellsmore

The bond between the rubber and inner casings degrades over time whether they have been driven or not. The result of this is a violent blow-out, where the tread and/or sidewall separates from the rest of the tire. Some tires that looked very good have exploded just sitting in a garage, and I've heard of some exploding in the spare compartment of the boot.

Bias-ply tires don't seem to have this issue but radials do. Everyone has their own opinion of course, but I try to never let a tire age over ten years, and preferably replace them at about 7-8 if I haven't worn them out yet.
Steve Simmons

Thanks Steve, I’d be interested to see any research papers done on steel belted radial side wall degradation, especially spontaneously exploding. Anyone seen any papers?
Mike
Mike Ellsmore

Mike
See extract from Continental Tyres website: Note the second sentence. https://www.continental-tyres.co.uk/car/all-about-tyres/tyre-damages/replacing-tyres
------------------------------

How many years will tyres last?
We are not aware of any technical data to support the removal from service of tyres past a specific age. But the same principle applies to the tyres of your vehicle as for any other part of your car – age matters.

Together with other members of the tyre and automotive industries, we advise that all tyres (including spare tyres) made more than ten years ago should be removed from service and replaced with new tyres.

In short, even though a tyre over ten years old may seem fine for driving, we still recommend getting new tyres for your car. Drivers cannot rely on visual inspection for rubber cracking, wear to the tread or other signs of deterioration due to age. While tyres may appear perfectly functional, their age is a factor for replacement.
John Francis

Hi John,
I am a bit of a contrarian when it comes to tyre replacement - I am interested in the facts as to why they should be replaced, not so much tyre companies recommendations.

I quote from the link you sent to Continental Tyres (note the second sentence).

"How many years will tyres last?
We are not aware of any technical data to support the removal from service of tyres past a specific age. But the same principle applies to the tyres of your vehicle as for any other part of your car – age matters.

Together with other members of the tyre and automotive industries, we advise that all tyres (including spare tyres) made more than ten years ago should be removed from service and replaced with new tyres."

It would nice to see these recommendations backed up by research or specific numbers like change in original durometer hardness but I guess it is not in their interest.

Cheers
Mike (on my second glass of red)
Mike Ellsmore

We know that tires age, and that when they age they sometimes fail violently. And when they do that, it's often on the highway. The fact that There is no way to tell if an old tire is still safe or not is more than enough reason to change them at the point where they become suspect. Generally speaking, that point comes at the age where they are generally recommended to be removed from service. Some really horrific accidents have occurred due to old radial tires blowing out. If you've ever seen huge chunks of tires laying in the road (and who hasn't) then you've already seen the reason to change them.

There's no way to tell when a snowy cornice is about to fracture and fall, but you still wouldn't walk on one. Same principle. Only in this case, the snowy cornice is going to kill other people, too. We know it happens (and far too often), so it's simply not worth the risk. That's my opinion and I'm sticking to it.

PS... There's a photo floating out there somewhere of an MGB that was driving on old tires which blew, and the car spun violently out of control and rolled. No thank you! New tires are cheap insurance.
Steve Simmons

I'm of the opinion that tyres do seem to "go-off" with age, in my experience, they do seem to lose some of their grip after a few years.

We were travelling in company with 3 other MGAs down a mountain pass in France a few years ago on wet roads after a fairly heavy shower.

I was driving at the rear of the three cars and I was having no problem with road-holding or grip and neither was the car at the front. But the car in the middle of us was having a really torrid time of it with the rear sliding about on many of the curves.

After almost being caught-out by the first semi-spin, the driver became used to this and was beginning to enjoy the controlled slides.

But I have to admit that his wife was not so happy about the experience!

When we looked closely at the tyres later, although they looked to be in perfect, almost as new condition, it turned out that they were around 10 years old.

We were all driving with virtually size and make radials, but the tyres on the other two cars were both less than 12 months old.

I drive my MGA up to 4000 miles a year (some years more) and I really enjoy how the car corners, so this means that I normally have to replace the tyres before they get old enough to go off.

Colyn
Colyn Firth

And not just the grip, but the ride quality as well. There is nothing you can do for so little money, to improve the performance and ride quality of a car, than to replace old tires.
Steve Simmons

You'll get varying replacement timelines from different tire manufacturers, and 6-10 years seems to be the recommended range. Tires, regardless of the remaining thread, will deteriorate as time passes: tires exposed to the elements will deteriorate faster than those which have minimal exposure and are stored indoors. But regardless of internal or external exposure, the tires will degrade. The chemical components which make up the tire do chemically interact with one another; add in heat, cold, ozone, etc. and the results can cause cracks, belt separation and loss of traction. Some of these can seen, others are a bit more insideous and can lead to catastrophic and unexpected failure. This is not an area to take a chance, especially if the tires are more than 10 years old. See link to an Edmunds article which discusses the issue:

https://www.edmunds.com/car-maintenance/how-old-and-dangerous-are-your-tires.html

As an example: attached photo is of a 6 year old tire that failed on an MGA back in 2018.


Nick Kopernik

In the archives you will find where this BGT owner wanted others to know, admittedly I think his tyres were a lot more than 7 years old but they looked good!

I sold a genuine original unused full-sized spare wheel and tyre that had been in the tyre well of the boot of the car from new, and both looked as new, it was 25 years old, I sold it to a model enthusiast as a show display item only. I can't recall now if they were later fitted to his car but I never suggest it or do it.

We make our choices but sometimes it can be others that pay for our mistakes, even when we don't.






Nigel Atkins

Tyres are a much underrated and undervalued component on a car, many don't realise how complex they are. For those that like roundy-roundy racing just consider how much time, effort and expense goes into the tyres they use and test with.

Tyres affect the braking, steering, road holding, handling and ride comfort and noise.

As they age and wear their performance reduces, why would anyone with a sports car with performance that's greatly reduced.

Summer tyres lose efficiency from 10c, a UK summer day let alone night can be 10c or less sometimes let alone the rest of the year.

There are many and complex elements that go into the reduction of performance (remember safety is part of performance) that you'd have a very wide range of possible ages for the tyres to last and give reasonable/acceptable performance. As has been put already, better to change before than after.

For classics I feel it's a combination of age and/or lack of use that loses a tyre's performance.

Shedded tread has a few possible causes most are about lack of maintenance or abuse or disregard to the consequences of suspect actions previously, often from lorries, trailers (caravans?).
Nigel Atkins



15 July 2013




Three people returning from the Bestival music festival died after a coach tyre that was 19-and-a-half years old blew out, an inquest heard.

The 52-seat coach crashed as it headed north on the A3 in Surrey, travelling to Merseyside from the festival on the Isle of Wight last September.

Driver Colin Daulby, 63, and passengers Kerry Ogden, 23, and Michael Molloy, 18, were killed.

A tyre expert told the inquest the tyre that burst was "abnormally old".

The blow-out, on the front nearside tyre, made the coach veer to the left, mount the embankment, crash through a fence and into a tree just before midnight on 10 September.

The coach, which was operated by Merseypride Travel, was full of friends who had left Merseyside for the festival five days earlier.

Passengers spoke of waking up and seeing the tree looming before them as the coach went up the embankment.

The inquest heard many suffered serious injuries.

Mr Daulby, from Warrington, Miss Ogden, of Maghull in Liverpool, and musician Mr Molloy, from Woolton in Liverpool, died from multiple injuries.
'Falling apart'

Tyre expert David Price said several of the six tyres on the coach were old, with the tyre that burst being "abnormally old".

Another dated back to 2001 and the spare was 14 years old.

The burst tyre had a dot code giving its age and caused the accident as it finally failed, he said.
Image caption The coach crashed through a fence and into a tree

He said the tyre had been falling apart internally for months.

Mr Price said it was only half worn so had either been a spare or in storage for many years.

"This is one of the oldest tyres I have encountered failing," he said.

He said recommendations from manufacturers said tyres should not be fitted to cars if they are six years old, and should be replaced if they are 10 years old.

He said that this was not a legal requirement and that it did not apply to coaches or lorries, which was "frustrating".

It just left the road. There were no brake lights, no skidding - it just glided off the road and then up the embankment
Janet Fields, Witness

'Struggling to walk'

Motorist Thomas Hughes said that as he had almost overtaken the coach, he heard a "very loud explosion".

His car swerved and was hit with debris that sounded like pebbles hitting his roof.

"I looked in the left-hand mirror because I thought I had blown a tyre and the coach was not there," he said.

Troy Walter was a passenger in a car behind the coach when it left the dual carriageway.

"There were a couple of people struggling to walk, there was debris on the floor," he said.

Janet Fields, who was driving Mr Walter, said in a statement: "It just left the road. There were no brake lights, no skidding - it just glided off the road and then up the embankment."

Mr Daulby was described as a safe and considerate driver who loved his part-time job with the company. Tests showed he had not consumed alcohol or drugs, the hearing was told.

The inquest, in Woking, Surrey, was adjourned until Tuesday.
Roger Walker

Incorrectly inflated and overloaded tyres and vehicles also hasten the demises of the tyres, and possibly people too.

I've seen an owner of a powerful and expensive sports vehicle insisted one (one!) medium price tyre be fitted rather than the specified tyre for the vehicle, these people drive on the same roads as us, and other poor devils.
Nigel Atkins

Just to correct a misapprehension ...

Nigel wrote "In the archives you will find where this BGT owner wanted others to know, admittedly I think his tyres were a lot more than 7 years old but they looked good!"

The car was mine, I got rid about 5 years ago.

If I said the tyres were 7 years old, then three of them probably were. The tyre on the rear offside however had been the spare and had no date marking. I suspect it was an original, in which case it was about 27 years old when it went pop!
R G Everitt

Sorry that was a typo I meant tyre, but I had forgotten the details (and your name, sorry).

The 7 years refers to another post rather than your tyres.

But I did remember you kindly said I could use the photo and story as a warning, thank you and I have.

Very, very unusually I've had a brainwave, as I can't rely on my memory to aid it I've tiled one photo as 'about27yearsold' and the other as 'R G Everitt' but I can change that if you want to 'about27yearsoldcu'.

Thanks.

What car do you have now?

Nigel Atkins

Nigel

No need to mention me, thanks.

After the MGB GT, I had an MG TF for 3+ years, then for last 1.5 years have had a BMW Z4. I must be getting old too!
R G Everitt

Thanks.

At least it wasn't a Z3. :)
Nigel Atkins

This thread was discussed between 28/09/2020 and 02/10/2020

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