Not long until the winter tyres go on!

[R2D2]

How long until we get to only 7c and the winter tyres go on? Last year I changed to mine on 1st November...

 

[Dieselman]

Is there evidence, other than internet myth, to suggest that 7c is the magical temperature point?

Surely, once tyres are in use they get above 7c within a minute or less.

Someone on here once commented that 2c was the temperature when Winter tyres started to have better grip.

 

[R2D2]

The AA say :
"Winter tyres use a tread rubber compound (high silica content) and tread pattern specifically designed to retain flexibility in low temperatures (below +7C) and give good braking/traction performance on snow/ice as well as on wet roads in cold conditions ."

 

[Dieselman]

Anything to back the AA advice?

Michelin use high silica content to reduce wear. Does that mean their tyres work better in cold conditions than other brands?
They are always noted to be more compliant.

 

[joecash]

Personally I think it's all a con to get people to part with their cash for wheels and tyres - never used to be this much paranoia over winter and summer wheels or am I getting old and well past it?

 

[R2D2]

Anything to back the AA advice?

I think they know that I change mine at 7c and just decided to copy me

 

[Dieselman]

I think they know that I change mine at 7c and just decided to copy me

Probably.

I suspect that is how most semi-official information comes about. It then hits the media and web and it's suddenly "official".

 

[Deleted member 65149]

There seems to be plenty evidence that Winter tyres are better at low temperatures and/or on snow. But my concern is that I've read reports on tests that show their performance to be vastly inferior on dry roads when above 7C. We get winter temperatures much higher than this from time to time (eg 11 December 1994 in Staffordshire 17.7; 27 January 2003 in Kent 17.6; 13 February 1998 in London 19.7). My fear is that people on winter tyres under those conditions will be less alert to the inferior performance of their tyres and thus more liable to get into trouble. In many parts of the world winters are reliably cold and snowy, so winter tyres are essential. But our weather isn't so predictable nor so severe, so I still doubt the need or safety of winter tyres here. I certainly wouldn't want to be changing my tyres on an almost daily basis dependent on the weather forecast. Does the ability to get around more easily once or twice a year at most outweigh the cost and potential dangers of winter tyres on good roads?

 

[grober]

Tyres with high silica content convey several advantages other than cold weather performance. The principle one being reducing rolling resistance= less fuel used. More and more manufacturers are adopting higher silica content for this reason. The people with most experience in this type of tyre chemistry I would venture are those who already have a long history in the winter tyre market- Vredestein, Nokian and Michelin although no doubt others are catching up. Certainly if looking for a summer tyre that will perform better in cold conditions a tyre advertised as having a high silica content would be a good bet. [ the advertising would probably emphasise the low rolling resistance bit rather than the cold weather aspect mind] High silica content would perhaps cover the "cold temperature" aspect of winter motoring but not obviously the slippery/moveable surface aspect of snow/slush and ice best dealt with by the tread pattern of winter tyres. I suspect also that proper winter tyres defined by the snowflake symbol may have a higher silica content than the summer low rolling resistance/high silica tyres but since manufacturers don't publish the chemical make up of their products that's mere speculation on my part.
I bet this research was sponsored by Vredestein for example .

http://doc.utwente.nl/38015/1/t000003d.pdf

 

[grober]

But my concern is that I've read reports on tests that show their performance to be vastly inferior on dry roads when above 7C.

You have made a pretty strong assertion there. Personally I feel it is extremely misleading and might be a source of worry to people reading it who have winter tyres on their car. In the interests of clarity I would be grateful if you could provide a link to any such evidence so people can decide for themselves. I speak as someone who has run winter tyres all year round Vredestein/Nokian/Michelin for the last 15 years and honestly never experienced the problem you describe.

 

[Dieselman]

I speak as someone who has run winter tyres all year round for the last 15 years and experienced none of the problems you describe.

As a result you may have come to expect reduced tyre performance.

Winter tyres are known to offer reduced warm weather grip and handling feel, which is why they are speed limited.

 

[Sp!ke]

Anything to back the AA advice?

Michelin use high silica content to reduce wear. Does that mean their tyres work better in cold conditions than other brands?
They are always noted to be more compliant.

I think a high silica content does help but it works in combination with a more horizontal and blocky tread pattern with more sips in the blocks.

Compare a Michelin summer tyre to a winter one and the tread design difference, is marked.

Michelin Summer

Michelin Winter

Michelin High performance 4 season

 

[Dieselman]

I think a high silica content does help but it works in combination with a more horizontal and blocky tread pattern with more sips in the blocks.

Compare a Michelin summer tyre to a winter one and the tread design difference, is marked.

Undoubtedly, but there has been evidence in tests to say that some manufacturers summer tyres outperform others winter tyres in poor conditions.

My suspicion is that a not overly wide tyre with decent sidewall height and both sidewall and tread flexibility, coupled to a high silica content and flexible suspension will provide pretty reasonable traction and grip.

The modern problem seems to be cars with stiff suspension and wide, inflexible tyres.

 

[Sp!ke]

These are the 4 season Goodyears on Mrs Sp!kes volvo. (Goodyear Vector EV2)

You can see that the outer tyre is of a summer design so that when cornering hard you have solid blocks that dont squirm when driven hard but the inner tread is of a winter design aiding traction and braking. Dual compound rubber too.

I suspect the theory is you dont have the lateral forces on snow so the outer tread blocks arent as significant in these conditions.

What I do know is these tyres work very well indeed. I think they are the best all year round tyre type for our climate.

 

[Sp!ke]

I also know that if you have heavily summer biased tyres like Eagle F1's below, dont bother driving your car in the snow at all. (I couldn't get over a slightly raised Give Way line without a runup)

 

[Sp!ke]

Undoubtedly, but there has been evidence in tests to say that some manufacturers summer tyres outperform others winter tyres in poor conditions.

I've not seen this - can you still find a link?

 

[Dieselman]

I've not seen this - can you still find a link?

I'd have to look more deeply, but the first test I came across:

2012 Auto Bild 42 Winter Tyre Braking Test | the online tyre guide

It doesn't specify what the summer tyre is.

This test also highlights the poor performance of budget winter tyres in the wet.

The average budget winter tyres sacrifices too much wet performance to be considered a sensible option for the UK climate.

The Braking Results
Please note: Auto Bild considered places 27-42 so dangerous they did not test them in the snow. Our results show 1 meter for formatting reasons

As with most tyre products, you get what you pay for, only use branded products.

The BEST winter tyre took 1 meter longer to stop in the wet than the summer tyre, the worst took 17 metres longer to stop.


http://www.tyrereviews.co.uk/Article/2012-Winter-Tyre-Buying-Guide.htm

While Northern European winters are dominated by periods of heavy snowfall, here in the UK we tend to experience mostly cold and wet winters, which places a unique requirement on our winter, or cold weather tyres.

Any winter tyre will vastly outperform its summer equivalent on snow, with even the cheapest of winter tyres performing excellently on the white stuff, but the real challenge for a winter tyre is the balance of wet and dry performance, while offering a good snow ability.

 

[HB]

I think a high silica content does help but it works in combination with a more horizontal and blocky tread pattern with more sips in the blocks.

Compare a Michelin summer tyre to a winter one and the tread design difference, is marked.

Michelin Summer

Michelin Winter

Michelin High performance 4 season

You just like photos of rubber.

 

[gIzzE]

Tyre reviews, tests and ratings | the online tyre guide

Some winter tyres like Falkens performing worse than some hi end summer brands, and then some winter tyres from Dunlop that out performed some of the summer tyres in the summer.

I have forund Michelin Alpins perform excellently all year round, their Tourer all season even better, Dunlop Winter Sport 4D the same.

Someone who said we never used to worry about this?
Many cars were 195 wide wheels back then with a symmetrical tread, nowadays we have 255 wide or wider on asymmetrical treads and 450nm of torque instead of 120nm, and the cars weigh twice as much, got to compare apples with apples.

Winter tyres make a huge difference, if they are good.



600km in 6hours with the 2 inside lanes of the autoroute under drifts, I was passing cars in the drifts, even 4x4's, and got to Calais nice and fresh, not stressed out.
That was in a RWD C Class estate.....

I tend to leave mine on from Nov-Feb, sometimes Oct they go on and sometimes stay on till March.

 

[Sp!ke]

I'd have to look more deeply, but the first test I came across:

2012 Auto Bild 42 Winter Tyre Braking Test | the online tyre guide

That is an odd article - what temprature was it during the wet tests?

Also, how come the braking distances are shorter in the snow than in the wet?