Tyres wear on the edges

Feb 13, 2011 21 Replies

I went to Honda for a recall on my 2004 Accord. While they were at it, they checked the tyre treads, which were as follows:



N/S/F 5.5; 6.3; 5.4 O/S/F 5.7; 6.9; 6.0



The rears are 6.3/6.2 N/O resp. across.



Under-inflated, I hear you say. I checked them with my air compressor gauge; 0.5 PSI off, that can't be it, on tyres that are 6 months / 3-4K miles old, can it? And if the gauge is off, why are the rears fine? Anyway, recommendations for reliable gauges at a reasonable price are welcome.



What else can cause such wear?



Thanks,



Kostas


IME, tyres always wear faster on the edges than they do in the centre.

It's to do with contact patches under cornering, which is when tyres wear fastest.

Not me. "Steering" I hear me say.

Thank you (and SteveH). Does steering eat into the inner edges as well?

Kostas

the nearside tyre wears out first usually due to the large number of roundabouts there are. both edges of both front tyres are hit by cornering forces far more than rears are.

It is highly unlikely that a gauge on a compressor will be accurate, since generally an accurate gauge on its own would cost more than little compressors. Generally digital gauges seem to be more accurate than mechanical ones. I would recommend a digital gauge by michelin if you can, about 25 quid. this is the one I use:

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Hi Kwsta,

If it has too much toe-in it will wear out the outer edges.

If it has too much toe-out it will wear out the inner edges.

Can't really have both (well you could if you drove half your distances forward and half in reverse or something like that), so I am tempted to say a good pressure gauge like you suspect is your starting point.

Not that it matters, what make of tyres are fitted?

Cheers Charles

PS. I had a SAAB 900 (circa 12-15 year old at the time) which was wearing out one outer edge (near side). When on a ramp being checked with a laser I could put it toe-in or toe-out by gripping the wheels and pushing, pulling them. Later on with careful looking I found I steering knuckle having a tiny bit of play, hard to spot. Replaced it myself (set the alignment myself ... i.e. hope for the best) and it stopped wearing out one edge.

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Nice toy. £21.48 at Amazon :-)

Charles

Kostas Kavoussanakis formulated the question :

Lots of hard cornering can scrub the sides too.

Manufacturer's tyre pressure recommendations are not cast in stone. Tyre make, vehicle load and other factors affect the ideal pressure. In any event you're generally better off running as high a pressure as you can get away with for best fuel economy which will more than pay for any extra tyre wear. In your case it seems you actually want another few psi in the fronts so it's win/win. I usually run 5 psi over the OE figure.

In article , Kostas Kavoussanakis writes

Many speed humps in your area?

In article , Dave Baker writes

Glad it's not just me that thinks that.

Aye, I will have a look at Mr Cheerful's suggestions (thanks Mr Cheerful).

6-mo Continental at the front, 18-mo Michelins at the back. 195/65VR15.

Kostas

Aye, a few. And because the car is used mostly in sub-urban conditions, they account for a sizeable chunk of its mileage, as do roundabouts, previously suggested.

Most of the speed-bumps I encounter are the split type and I tend to straddle them, so it's almost like they are not there (I don't speed where they put them anyway).

Kostas

(Long URL replaced, as my news server did not let me post:

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The short story: my compressor tends to indeed by inaccurate. However, I always went for 1PSI over recommended "just in case". I may go for a cheaper than the above, but considered accurate, gauge to balance it, but I think you have put my mind at rest; I just need to enjoy life less. :-)

So, looking for the above (whose price seemed, err, challenging), I came across this:

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It seems to recommend this:

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However, there is this (non-replaceable batteries):

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Autoexpress seem to also recommend this:

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However, my compressor is this:

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I can't help but wonder: will Ring (or any manufacturer) have different technologies for the same "simple" thing?

Cheers, Kostas

Interesting. I am aware of the economic argument, but 5 PSI on my recommended pressure (31) is quite a lot. Does yours have a higher recommendation? What would the insurance company say?

Kostas

The variation in recommended pressure for my rear tyres (from memory is about 5 PSI.

Because of edge tyre wear I have started running a pound or two higher.

In article , Kostas Kavoussanakis writes

That's where your tyre wear is coming from, then. I drive over the centre of the bump with the other pair of wheels on the gap in between.

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In message , Mike Tomlinson writes

This may be true, but some of the so-called "cushions" which surround where I live are so vicious in the middle that the jolt of passing one wheel over even at less than 20mph can throw the car in an unacceptable way. I'll look again at the tread figures supplied by my garage at MOT and service safety checks, but I don't think the inner edge wear is worse than the outer edge.

Ironically, by experiment, I found that straddling the pads at about

30-35mph was less of a jolt to the occupants, but as for the suspension... :-(

I had two Draper digital gauges (different models) that read 3 psi different to each other when testing the same tyre at the same time.

Assuming that you were testing at 30psi, and one gauge read 1.5psi low, the other 1.5psi high, that would actually be a really good result.

As oft-reported here by me ad nauseam, I tested a number of gauges some years back to laboratory standards. Some were out by 20%! The best was the cheapest Halford's digital one, although perhaps another sample of the same model might not have been so good.

As a rule of thumb, digital ones seem most accurate, and more likely to remain so over their lifetime. Pencil types are next best, but dial types, especially those fitted to foot pumps, are little better than kicking the tyre to see if it's flat!

Chris

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