Winter Wheels fitted

[I Feel Old]

Originally Posted by foggyjames

I don’t have any evidence to hand, I’m afraid. That’s not to say there isn’t any

I would suggest that winter tyres would offer excellent warm dry braking performance, as they tend to be a soft compound. It might wear them quickly though. I suspect that the “14%” test is against a tyre designed to excel in wet conditions - I’ve cerrainly never had summer tyres which would outperform winters in wet conditions (entirely subjectively), but it wouldn’t surprise me if something like Rainsports would.

“Wets” vs winters for the British climate is an interesting discussion point. I’m pretty convinced that the tyre industry doesn’t serve us well with the typical “summers”, though (he says, with a set of four on his V70!).

cheers

James

Good post James, as is the post my another V60. There just is not the all round scientific evidence readily available and that's my point. A lot of the coverts are basing their decision on gut feel and hearsay, which is fine, if only they could acknowledge that is the case rather than dismiss those seeking the scientific evidence.

For 95% of British drivers, they’d be better off with winters all year round!

As for that assersion, I think I'd need to see some evidence for that one!

If you found out your 18 year old daughter's new boyfriend was buying very cheap unknown Chinese condoms - you'd give him a clip round the ear. Why take risks with ditchfinders?

Interesting analogy, Tannaton. Sounds as though you've had those sort of worries.

Originally Posted by MaDProFF

I do not recall ever saying you were inexperienced at driving, or what you were talking about in driving, what I said is until you have actually driving on winter tyres (Good ones) you cannot appreciate how good they really are, to base some of your comments

Ah, but you see MaDProFF there is more to understanding the issues than simply driving, important as driving is. And I think it's fair to say I've had my fair share of dealing with the other end of drivers' lack of ability to keep it on the road (see image as example) and I can assure you it is not all ice, snow, or winter tyre related.

Originally Posted by MaDProFF

Anyhow, as some other poster pointed out it has got a little boring now

That's a shame you have opted out without addressing any of my questions asking you to point me in the direction of the evidence for the accusations you throw in my direction. I'll take it you accept the accusations as having as little evidence as your arguments for the suitability of winter tyres throughout the winter, regardless of how severe the weather is?

Now wouldn't it be fun if the contributors to this thread could all get together with the appropriate equipment and conduct our own experiments?

[Deman77]

Winter tyre soft compound is awful for dry breaking in high temperature. It is much more likely to overheat than summer - when it melts and you end up skidding - the kind of effect you get when ice skate glides on ice - friction melts the ice and you have it slide through water instead of scraping through dry ice.
Winter tyres do relatively ok in wet high temperature as water reduces overheating.

[Tannaton]

Originally Posted by Deman77

Winter tyre soft compound is awful for dry breaking in high temperature. It is much more likely to overheat than summer - when it melts and you end up skidding - the kind of effect you get when ice skate glides on ice - friction melts the ice and you have it slide through water instead of scraping through dry ice.
Winter tyres do relatively ok in wet high temperature as water reduces overheating.

Winter tyres are softer - I don't think anyone would dispute that - but they don't "melt"...

[I Feel Old]

To take it to the extreme momentarily; think F1, wet tyres have 'blocks' of rubber to disperse the water, it's soft and flexible and consequently moves a lot and in doing so generates heat. The tyre needs the water for cooling, when it dries they overheat and become ineffective. They don't actually have to 'melt' for that to happen.

The same must happen, albeit to a much lesser degree, on ordinary car tyres even although there is always a compromise needed for road tyres, whether summer or winter.

[MikeGMT]

Lots of technology go into tyres and it's a complex subject in it's own right. I've read a few technical articles and to be honest a lot of it is beyond me.

Basically the tyre lays down a thin layer of compound onto the road, and because the road and the tyre are made of the same compounds, 'hydrocarbons', a chemical reaction occurs and bonds the tyre to the road surface. More load on the tyre increases the surface area of the rubber and more grip is produced. Ergo wet roads produce less grip, snow and ice even less or non, as the chemical bond is not achieved. Thats only a rudimentary outline, it's a lot more complex than that.

I think a lot of people don't realise what those black rubber circles with a contact patch the size of your foot are doing as they get you from A to B.

[chrisrixy]

I can't believe this thread has got to 17 pages of discussion!

As pointed out - until you have driven on good winter tyres in cold wintry conditions if is difficult to understand how good they are in these conditions. I've had an XC90 on summer tyres in snow and it couldn't get to my house - but with winters on the same car and more snow/ice I can drive to the door.

Are they as good in warm wet conditions as a summer tyre? Probably not - although in this autoexpress test - the results in warm wet conditions showed the summer tyre to be only very slightly better than the best winter tyre.
https://www.autoexpress.co.uk/access...ts-by-category
The summer tyre was hopeless in the snow.

The contencious issue seems to be in wet conditions - but I suspect there is a greater difference in wet performance between a new summer tyre and one with minimal tread at the legal limit, than between a good summer & a good winter tyre. As you should replace winter tyres at 3 or 4 mm tread they should always be better than a summer tyre on the legal limit..not science, just common sense.

We can't really change our tyres as often as we change our shoes (we don't normally wear sandles in winter or wellies on hot summer days) so you have to make a choice on what is the best compromise overall given your personal circumstances.

I will continue to switch from winters to summers - which I feel best suits the conditions I expect in the highlands. At times I might have the 'wrong' tyres fitted and will drive accordingly. Most of the time I hope I will have the right tyres.

A bigger compromise would be to fit all-season tyres - not as good as winters in winter or summers in summer - but probably ideal in spring & autumn!

I would rather drive through the winter with a possible minor loss of performance if it is warm & wet rather than find the car is barely drivable if I meet any snow & ice.
When it is snowy I'm almost more concered about being hit by another car that is being driven while not suitably equipped by the owner, than sliding off the road myself. Driving on summer tyres in snow & ice is asking for trouble - especially in hilly areas. If you think you will need to drive somewhere when it might be snowy then buy winter tyres. The cost is so minimal (assuming you keep a car long enough to require at least 1 new set of tyres while owned) that it seems a good idea. Otherwise wait for the snow to melt away...

[Crockers]

There is the old maxim I heard when sailing.

"It's better to be in port wishing you were out at sea than out at sea wishing you were in port"

[Deman77]

Originally Posted by Tannaton

Winter tyres are softer - I don't think anyone would dispute that - but they don't "melt"...

Tyre skid marks is actually melted rubber. The reason they don’t grip when skidding is because you are effectively sliding on melted rubber.
The point is winter tyre will be at its worst on a hot dry road not extremely grippy as someone indicated earlier at least not for the load levels required to stop a car.

[ergonomist]

I'm curious, I Feel Old, as to what sort of data would satisfy you - I suspect it will never be available (but I find this thread interesting because of the challenge that presents). The point has been well made in many posts that the performance of tyres is affected by a complex and interrelated set of variables (temperature, wet roads, type of tarmac, etc). Consequently it would be very difficult to undertake truly comparative double-blind comparisons of different tyres that cover all conditions.

In terms of statistical evidence - perhaps the insurance companies would be best placed to provide that, except they don't collect the data on type of tyre to correlate with accidents.

Which leaves us with subjective data - and this 'debate'. My impression is that all of those posting here who fit winter tyres each year perceive a net benefit from such tyres. But I Feel Old would rightly dismiss that as skewed data - if you've invested approx £1k on winter tyres you may be biased towards perceiving benefit.

My perception is that this debate has moved away from 'are winter tyres better in snow etc' and more towards 'is there a net benefit during winter months in having winter tyres, in the UK'. I tend to go onto winters in November and change back to summers around March. So a question becomes - will I encounter conditions during that period that put me at greater risk by being on winters? The answer must be 'Yes'. But the inverse also applies - will I encounter conditions that favour winter tyres? The answer to that also must be yes. Hence the critical question I would want to answer, in my discussions with I Feel Old, is the probabilistic one of whether the benefit of the many days when winter tyres are preferable during the Nov-March period outweighs the increased risk during the days when summer tyres might perform better. My (personal) view is that the net benefit is in favour of winter tyres - in very cold weather they are significantly better, and in mild winter conditions they are likely to be only a little worse, and there will be fewer days when that applies. Indeed, I Feel Old has made this sort of argument in another thread - Time at Risk being used to justify HUD rather than Heated Screen.

However - I don't have hard data to support this personal judgement. I have semi-deliberately used value-laden words such as 'significantly better' and 'only a little worse'. I will never be able to substantiate those judgements - they are simply my personal view. It would require a level of meteorological data that I suspect none of us have access to, and also a level of quantification of tyre performance under different road and weather conditions that simply isn't available.

Which therefore leaves us where we were many posts ago - fitting winter tyres in the UK is a personal decision. Those of us who do reckon there is a net benefit. But none of us will be able to provide quantitative data to make an argument that is incontrovertible. And that's why I would never insist that everyone in the UK fits winter tyres, but also why I will always do so.

It is entertaining, though, seeing how the request for a compelling argument is causing so many furrowed brows. It encourages an interesting discipline...

[Tannaton]

Originally Posted by Deman77

Tyre skid marks is actually melted rubber. The reason they don’t grip when skidding is because you are effectively sliding on melted rubber.
The point is winter tyre will be at its worst on a hot dry road not extremely grippy as someone indicated earlier at least not for the load levels required to stop a car.

Yeah but on modern cars with ABS, traction control and stability control etc. how often do you lock the wheels??