Tread depth - new tyres

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mointainwalker

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I bought myself a new set of winter-tyres the other week ( Avon WT7 195- 65 x 15) and decided to measure the new tread depth. I do this because I change winter/summer tyres during the year and like to keep some kind of record of wear.

Last time I did this with a set of Nokian several years ago ( very good Finnish winter tyres )the tread depth was about 6.5/7.0 mm, but to my surprise the Avons had 9.0 mm. This was a surprise because I assumed that there would be some kind of standard or industry agreement about this kind of thing. It also surprises me that - if this is the case with other tyres - that manufacturers aren't advertising " 2 MM more tread " in the way of that old petrol advert about getting more miles with "Petrol X ".

Anybody got any comments, know any web-sites that might give information of this ?
 
Probably the same reason (for example) soap dispensers make it very awkward to eek out the last few mm of soap because the tube's a tad short, or funeral prices are pretty much the same wherever you go.
 
Normal road tyres have 8mm from new and winter tyres have 9mm as you're expected to replace them before you get to 1.6mm so therefore the extra 1mm is to cover this
 
Another problem, is that there are lots of compromises in tyre design. Deep tread means less sharp handling as the tread blocks just squirm around. It also means more noise (usually). Of course, there's no reason to be certain that Brand "X", with 9mm of tread is going to last longer than Brand "Y" with 8mm of tread, because Brand "Y" might be a harder compound.
 
A new set of Michelin cross-climates bought last year only had 7mm.
I've since removed them after finding they are bit noisy on the crap road surfaces we have to put up with these days.
The tyres are stored in the dark which will hopefully slow down the aging process, maybe I'll have them re-fitted in the (unlikely) event of a future bad winter.
 
mointainwalker said:
I bought myself a new set of winter-tyres the other week ( Avon WT7 195- 65 x 15) and decided to measure the new tread depth. I do this because I change winter/summer tyres during the year and like to keep some kind of record of wear.

Last time I did this with a set of Nokian several years ago ( very good Finnish winter tyres )the tread depth was about 6.5/7.0 mm, but to my surprise the Avons had 9.0 mm. This was a surprise because I assumed that there would be some kind of standard or industry agreement about this kind of thing. It also surprises me that - if this is the case with other tyres - that manufacturers aren't advertising " 2 MM more tread " in the way of that old petrol advert about getting more miles with "Petrol X ".

Anybody got any comments, know any web-sites that might give information of this ?
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Winter tyres wear faster - or at least they do in warmer temperatures.

The rubber compound is designed to be the right softness at winter temps.


Also you might find the winter tyres have sipes which are little slits - they grip in snow.

Winter / all season tyres lose their grip as soon as tread depth gets anywhere near the limit - if you want decent grip don’t go below half depth
 
I have a set in the dark garage, and they have lasted much longer than the set on the car. I happened to get one out while I was having a repair done, rather than use the space saver. Depending where you live, you may do a lot more mileage on summer tyres. I do also treat them with Armorall, which is alleged to protect against UV aging, and makes them look pretty.

Much more convenient to have them fitted to a spare set of rims.
 
My Continental Sport Contact 5 SUV's had 7mm on form brand new.

As said, depends on construction of tyre, design of tread block, tread compound etc.
 
Notch7 said:
Also you might find the winter tyres have sipes which are little slits - they grip in snow.

Winter / all season tyres lose their grip as soon as tread depth gets anywhere near the limit - if you want decent grip don’t go below half depth
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I think you'll find that ALL tyres specified as winter-tyres have those (sipes ). I disagree about the tread depth ( unless you are only talking about winter use ) as the softer compound will tend to give better grip ( hence more wear ). One or two countries - Austria being the most notable - do have winter-tyre wear limits of 4mm ( you'll see TWI's with a snow-flake ), but I'm sure that's because the tyre co representatives strong-armed/bribed the government of thirty or more years ago. This fact is reinforced by it being illegal to use winter tyres outside the prescribed "winter " dates, just to make sure you can't use up any of those 4mm ! Austria has long been renowned for its corrupt governments.
 
JohnD said:
I have a set in the dark garage, and they have lasted much longer than the set on the car.
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Goodness John, next you'll be telling us that the car you don't use gets much better fuel economy than the one you do !:LOL::LOL:

JohnD said:
Much more convenient to have them fitted to a spare set of rims.
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Naturally. Also saves £10 + per tyre change and balance plus wait at the garage.
 
Keithmac said:
My Continental Sport Contact 5 SUV's had 7mm on form brand new.

As said, depends on construction of tyre, design of tread block, tread compound etc.
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Well, it is nearly always Continental and Nokian (Finnish ) which come out top in the winter-tyre tests in the German/Austrian motoring-club reviews.
 
mointainwalker said:
Well, it is nearly always Continental and Nokian (Finnish ) which come out top in the winter-tyre tests in the German/Austrian motoring-club reviews.
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I was happy with handling wet and dry and snow/ ice etc, wear rate was OK. They're not cheap but you get what you pay for.
 
Been very happy with Cross Climates on the Honda FR-V.

And the lads' car is wearing Bridgestone A005 Weather Controls, they're really good too. Better wet grip than the CCs.
 
Keithmac said:
I was happy with handling wet and dry and snow/ ice etc, wear rate was OK. They're not cheap but you get what you pay for.
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They cost me around £50 per tyre for 15" which isn't much beyond other tyres, so I am fairly happy with that .
 
Ours were £150 a corner, was a bit painful handing the money over!.
 
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