Are my tyres safe?

[crashbarrier]

I store my wheels in very similar bags to the Heyner(they may actually be made by them) but sourced them from Mr Winter Wheels when I got my, yes you guessed it, winter wheels for my BMW. Great bags and very sturdy as you can happily lift a wheel up by the handle with no fear of the bag letting go. And you'll save £6 as they are £34/free delivery. You don't get the little pouch but then you will never use it as the bags will always be on wheels.

Wheel Storage Set

[osbourne one-nil]

Top marks to Bridgestone for their quick, thorough and reassuring response....

Thank you for the photographs of the Bridgestone tyres fitted to your car.

Concerning the ‘cracking’ in the tyre tread grooves; this we have seen many times in the past (across many products, and most brands) where the top layer of surface rubber begins to oxidise and appears perished. We refer to this as ‘crazing’, as ‘cracking’ generally relates to splitting after force or trauma during operation.

The visible surface rubber crazing on your tyres is very minor and will pose no detriment to the vehicles safety of tyres performance.

It is worth noting that as part of tyre manufacturers’ compliance to environmental responsibility legislation, there are increased restrictions on the materials used in tyre construction.

‘Crazing’ can also be caused by other factors:
• Extended exposure to sunlight. (UV light dries out the anti-aging oils in the rubber which give a tyre it’s tackiness and elasticity).
• The application of ‘Tyre Dressing’. - Used by dealer forecourts and carwash companies mainly to make the sidewalls/shoulders of the tyres look ‘more black’. These can be quite strong and some are even mildly corrosive if used consistently over time.
• Poor pressure maintenance during the tyre’s life. This causes over flexing in the tyre casing eventually causing tyres to prematurely age.
• Exposure to contaminates. - Petrol, anti-freeze, motor oil, tyre ‘dressing’ (used on the sidewalls to appear more “black”).
• Regular, but short frequent trips in the vehicle (lack of use), where the tyres are heating up, then cooling down over a short period of time. (essentially preventing the aforementioned oils from percolating/migrating throughout the tyre fully). We add anti-aging oils into the rubber compound, however for these oils to be released the tyres need to get to an operating temperature. If the tyres are not used regularly then the releasing agents in the anti-aging oils are unable to percolate through the casing and ensure the tyre stays subtle.

The upside to this phenomenon is that ‘crazing’ only affects the top cap layer of rubber, so is only cosmetic in nature. - This type of appearance does not have any effect on the tyres handling or performance, and based on the appearance in the image provided we would advise that these tyres are ok to continue running. However as with any appearance-based condition reported in the market, we always advise to monitor the tyres regularly.

Please note that we take safety very seriously and we would never recommend you to continue using tyres that we thought were unsafe to use.
In their current conditions the tyres will not cause any detriment to the tyres serviceability or affect the cars dynamic performance abilities. If the tyres are well serviced and the correct tyre pressure is maintained the tyres will continue to provide an excellent service life.

We hope this info has helped, please let us know if there is any more info you require on this subject to assist with your enquiry.

[XC90Mk1]

Originally Posted by osbourne one-nil

Top marks to Bridgestone for their quick, thorough and reassuring response....

It’s very good of you to report back so we can all learn from that, thanks!

[Laird Scooby]

That's a very good and reassuring reply from Bridgestone. What i would infer from that is as you have minor cracking on the surface, when you start using the tyres, build the speed up gently, perhaps over a period of several journeys so they warm up gradually and start to move the anti-ageing compound round more and more.

I would guess also the cracks would slowly close up after they had been thoroughly warmed through from driving several times as well.

[met24]

Originally Posted by crashbarrier

Certainly, that's the case for my work vehicle which is a darn sight heavier and way faster than any Volvo or other car out there.

I'm guessing an aeroplane?

[Clan]

Originally Posted by osbourne one-nil

Top marks to Bridgestone for their quick, thorough and reassuring response....

In our cases I would say the cause from their list is:

• Poor pressure maintenance during the tyre’s life. This causes over flexing in the tyre casing eventually causing tyres to prematurely age.

I see this over and over on a daily basis in my daily routines ... not just a few psi down but 10 psi down long term ...

[crashbarrier]

Originally Posted by met24

I'm guessing an aeroplane?

met24, you're good at this. Gold star for you.

[Laird Scooby]

Originally Posted by crashbarrier

met24, you're good at this. Gold star for you.

In fairness there's not much else that fits the description! Also the tyres on an aircraft are probably only used for about 0.01% of the total journey, admittedly under high stress during those times.