Cracks in sidewall of tyre

drpau · Post by **drpau** » 27 Apr 2006, 22:25

Decided to check out how much friction material I had left on my brake pads earlier and when I looked at my tyres on the front, they both have these cracks in

Got the tyres last Feb. That doesnt look too safe to me. What does everybody think? They are Avon ZV3's,

bencowell · Post by **bencowell** » 27 Apr 2006, 23:02

I'd bin them!

citronut · Post by **citronut** » 27 Apr 2006, 23:09

they dont fail the MOT untill you can see the cord,so thats a good rule of thumb
regards malcolm

Jshodgson · Post by **Jshodgson** » 27 Apr 2006, 23:11

I got 4 tyres and tracking at Kwikfit for £143 so for £65ish I'd replace them for new.

BonceChops · Post by **BonceChops** » 27 Apr 2006, 23:12

I would not use them. Have you checked your tyre pressures? It looks like you have wear on the outside edge but is bad to see properly. How many miles have they done? If not many i would think about contacting Avon as it could be a manufacturing fault. I used to work for Michelin in a manufacturing plant and I know that customer services would often examine used tyres with possible defects so it might be worth contacting Avon and see what they say. It is not the usual UV light causing cracking you get on old tyres.

Incase anyone is interested as to why the sidewalls crack on old tyres I will try to explain. The rubber has waxes added that protect the tyre from the UV light in sunlight. As a tyre ages the wax migrates to the surface of the tyre to keep replacing the wax that is lost while driving around. When you see UV light cracking on tyres all the wax has migrated and been worn off allowing the sunlight to damage the surface of the tyre. Yes I know I am sad

BonceChops · Post by **BonceChops** » 27 Apr 2006, 23:16

citronut wrote:they dont fail the MOT untill you can see the cord,so thats a good rule of thumb
regards malcolm

Before you can see the cord water may be able to penetrate to the steel fabric. This will cause the steel fabric to rust and swell which can 'unstick' the fabric from the rubber causing the tyre to blow out.

drpau · Post by **drpau** » 27 Apr 2006, 23:36

I try and keep the pressures checked, according to the tread indicators they have worn quite evenly over the width of the tyre. Just a bit of a suprise as they are not very old (but I would say they are about a mm from the tread indicator). I did try and have a look for warranty info on Avons website but there isnt anything on there.

A blow out is a scary prospect...

BonceChops · Post by **BonceChops** » 27 Apr 2006, 23:45

phone them and ask if you can email them that picture.

James.UK · Post by **James.UK** » 28 Apr 2006, 00:09

Its not worth a possible risk to your life for the sake of driving on iffy tyres.

Be safe, get them replaced

I found similar cracks on my old tyres

and although they were a long way from being illegal, I replaced them all... Safety first.

mezuk04 · Post by **mezuk04** » 28 Apr 2006, 08:28

Have them replaced but keep the old ones in the hope of getting your money back.

ACTIVE8 · Post by **ACTIVE8** » 28 Apr 2006, 10:08

BonceChops wrote:I would not use them. Have you checked your tyre pressures? It looks like you have wear on the outside edge but is bad to see properly. How many miles have they done? If not many i would think about contacting Avon as it could be a manufacturing fault. I used to work for Michelin in a manufacturing plant and I know that customer services would often examine used tyres with possible defects so it might be worth contacting Avon and see what they say. It is not the usual UV light causing cracking you get on old tyres.

Incase anyone is interested as to why the sidewalls crack on old tyres I will try to explain. The rubber has waxes added that protect the tyre from the UV light in sunlight. As a tyre ages the wax migrates to the surface of the tyre to keep replacing the wax that is lost while driving around. When you see UV light cracking on tyres all the wax has migrated and been worn off allowing the sunlight to damage the surface of the tyre. Yes I know I am sad

So it's like sun cream for car tyres !

ACTIVE8 · Post by **ACTIVE8** » 28 Apr 2006, 10:11

Although tyre black is used as a cosmetic dress up for tyres, does the fact that it's a coating on the tyre, mean that it helps protect a tyre from UV damage ?

ACTIVE8 · Post by **ACTIVE8** » 28 Apr 2006, 10:20

Attend to it, get them replaced, but keep the old ones, and contact the manufacturer, and see what response you get it's better to be safe than sorry.

Kowalski · Post by **Kowalski** » 28 Apr 2006, 10:47

UV causes surface crazing, the UV can't penetrate very deep into the rubber, it only affects the very surface. I've had tyres with surface crazing and been perfectly happy to drive with them in that state.

What you have however is most certainly not surface crazing, you've got what looks like quite deep cracking. Looking at where the cracking has happened, its in the same place on three different tread blocks, its a weak spot where the tyre is thin but also its an area of stress concentration. This looks to me like either bad design or a manufacturing fault. If you run a tyre overloaded or overinflated they overheat, this makes the surface of the rubber a sort of matt finish, I can't see that in the photo so my best guess is that you've got a duff tyre.

drpau · Post by **drpau** » 28 Apr 2006, 12:16

Ironic isnt it, I had the receipt for these about 3 weeks ago and can I heck find it now! Just checked my Citroen booklet now to confirm I havent been over inflating them.
When I find the receipt Im gonna get in touch with them, or maybe its best to go back to National tyre?