My car's offside rear tyre has a shallow dent in the sidewall, about 0.6 mm (estimated) deep and about 15 mm across. I suspect it was caused about a week ago when I was slowly reversing on a friend's drive and caught the sharp corner of a concrete kerb-like border edging stone. When I first noticed the dent it was much deeper and wider than it is now. I assume that the tyre's steel reinforcement was deformed inwards and that it has gradually returned to closer to its normal shape.
If it was yours, what would you do about it? I'm concerned about the safety aspect but don't want to buy a new tyre unnecessarily.
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Are you looking at a 3 pointer Brian (Magic Roundabout)?
Con and use says offence if:
the tyre has any lump, bulge or tear caused by separation or partial failure of its structure;
Consider pdq visit to Tyre Shop and have it examined proper like.
dvd
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To be on the safe side, why not change it for the spare?
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Difficult to know whether there is unseen damage or if the properties of the tyre might be affected under load or when you're asking a lot of it. Tyres are relatively cheap in the big scheme of things and are so safety critical I would probably change it to be sure. Then next time you're doing 80 down the motorway with 5 people in the car, you can be a little more assured you did the right thing!
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I'd hazard a guess that catching the offending sticky out bit has broken a sidewall band L'esc, unlucky that but well spotted young man.
Unless it's a hundred pound virtually new tyre it's not worth repairing.
A proper tyre repair shop could vulcanise in a radial patch on the sidewall, but i have no idea of the current cost of such work, and those capable are few and far between, most of them are in Northants.
I too would sling it TBH.
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>If it was yours, what would you do about it?
Leave it and keep an eye on it - reasoning that if the structure was damaged it would be bulging out not in. I take it you really mean 0.6mm - a bit less than a spark plug gap? How did you detect it?
Note that I have answered the question - I am not qualified to advise anyone else on tyres ;-)
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Take the wheel off and see if there is a corresponding dent on the inside of the tyre too, the dent could be an oversize joint in the manufacture of the carcase. Is it a premium brand tyre or a cheapie?
If the tyre is damaged then it should be replaced and not used a the spare.
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Is it a premium brand tyre or a cheapie?
195/60 R15 88V Goodyear Eagle NCT5.
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I take it you really mean 0.6mm - a bit less than a spark plug gap? How did you detect it?
I put the edge of a 150 mm long steel rule across the dent and estimated the gap between the edge of the rule and the middle of the dent. I suppose I could have used my feeler gauges to try to actually measure the gap.
Edited by L'escargot on 20/09/2009 at 08:36
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I go by the rule:
Little dent in is OK, little dent out is not.
DinUK
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Little dent in is OK little dent out is not.
Discovered a little dent out in a front tyre last week, was wondering what to do about it, then read this - replacement fitted this morning. Thanks.
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I assume that the tyre's steel reinforcement was deformed inwards and that it has gradually returned to closer to its normal shape.
How large was the original deformation?
There's no steel in the sidewall.
I'd just keep an eye on it from time to time.
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There's no steel in the sidewall.
Its not the norm but sometimes there is metalic fabric 18 - 20mm wide near to the bead area, taxi, van and 4 X 4 tyres usually
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If it was yours, what would you do about it?
Replace it ASAP.
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Replace it ASAP.
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If you look at the sidewalls of a budget tyre you'll see bumps and hollows when new, even quality rubber can have them. Apply tyre polish to your own tyres and stand to one side looking down the flanks of the car and you'll see them.
Tyres are built in layers, every layer has at least one lap joint, some have 2 or more joints, the only exceptions are the metallic fabrics which are butt to butt
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>>..a shallow dent in the sidewall, about 0.6 mm (estimated) deep>>
About 0.6mm...
You cannot be serious? ..:-))
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About 0.6mm... You cannot be serious? ..:-))
Why do you say that? It's a dent which wasn't there before, and it was much deeper than that when I first noticed it.
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>>Why do you say that?>>
Are you quite sure you don't mean a centimetre?
If you can spot a 0.6mm "dent" in a tyre then you must have 40:40 vision...:-)
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If you can spot a 0.6mm "dent" in a tyre then you must have 40:40 vision...:-)
A 0.6 mm dent 15 mm across is easy to spot with the naked eye, even for me wearing bifocal glasses. As I said previously, it was much deeper when I first noticed it. Assume the dent is circular in cross-section, and try making a drawing of it with a pair of compasses. I'm sure one of the mathematicians in the Backroom can tell us what radius circle you need.
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How large was the original deformation?
I didn't measure it.
I'd just keep an eye on it from time to time.
Thanks, I will do.
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Is it radial?
I have had tyres (Michelins and others) with six equally spaced radial depressions which correspond to the mould it came out of. Only visible in some light conditions.
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It's a dent which wasn't there before
Did you hold a ruler against all the sidewalls when you got the car then, to check for imperfections? ;-)
Sorry. FWIW I would be inclined to think that the depression in the sidewall is just a manufacturing imperfection, and that you're being a little over-cautious. Certainly I've clouted kerbs pretty hard before now (used to drive minicabs, it happens a lot) and never had a tyre let go either slowly or explosively.
Dave TD
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Is it radial?
195/60 R15 88V Goodyear Eagle NCT5.
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>> Is it radial? >> 195/60 R15 88V Goodyear Eagle NCT5.
No - I said is it radial (as in radial or circumferential or random)
Not is it a radial!
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Putting this in perspective, there is approx 2 bar pressure inside the tyre (2 times atmospheric pressure) and 1 bar outside of the tyre, if the carcase was damaged you'd expect the tyre to bulge out would you not?
Jack the wheel up, spin it and observe any deviation of the tread.
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If this was my problem - and a 'safety' one at that - I would not spend 4 days on a thread discussing the matter with other people. If it's a genuine concern, get down to a trusted supplier & get it checked would be my advice.
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.......... get down to a trusted supplier & get it checked .........
I would think the only way to have it checked would be to have the tyre removed and inspected from the inside, in which case I'd sooner spend the money on a new tyre. Incidentally, I still think I'm justified in seeking the opinions of the Backroom.
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No - I said is it radial (as in radial or circumferential or random)
I would say the dent is more circumferential than radial, but only marginally.
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if this gaping chasm had been on the inner tyrewall we wouldnt be having this discussion... I wouldnt lose too much sleep over it if i were you
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>>..this gaping chasm..>>
All 0.6mm of it...:-)
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