Winter tyres - mini review.

[moonloops]

As seen as there has been some "healthy" discussions on here recently I thought I would jot down my findings so far.

Firstly I have been running Michelin pilot sports and the rears were getting just about down to the tread wear indicators. Fronts had wear on shoulders due to my front ball joints been worn (now fixed).

I made the decision to switch to winter tyres on my 17" (slightly grubby) wheels and plump for new 18" wheels and tyres for summertime use next year.

So I ordered a set of 4 Kumho KW27 225/45 R17 94V XL M+S from mytyres.co.uk they cost £94 each fully fitted and were delivered on time to a local tyre depot without any fuss.

Road Noise

No appreciabledifference in road noise If anything a slight whooshing sounds but I am being picky as the wind noise at speed is more noticeable.


Dry Roads, cold weather use (sub 5 degrees c)

Not as much initial turn in grip as the michelins (to be expected) but the grip is there. If I gun the throttle on take off there is a chirp/squeal (Michelins just span with no noise) before ESP kicks in.

Greasy cold roads / salted roads etc (again sub 5 degrees c)

Very little grip, borderline dangerous. You can do nice four wheel drifts at 15 to 20 mph on roundabouts without even attempting them.

On a private road I had ESP light flashing in a straight line at 80mph to 90mph. Not sure what to make of that, but not something to be proud of..

On Snow

OK so only about an inch of snow around but the Kumho's absolutely make a marked difference on snow. The exit of my road on to main road is slightly uphill and the surface gets "polished" by people spinning their wheels to get out. On summer tyres all I could do to get out was put auto in W mode and let the car idle its way out as any attempt at throttle would see you sat there or going backwards.

So on winter tyres I got to the junction, nothing coming and pulled out with a gentle press of the accelerator, one small flash of ESP and then the car pulled out without any fuss or traction issues.

I then went to hunt down a bit of open space (car park) that had fresh snow to test the grip. Auto box in S mode this time, from standstill I gave the throttle a bit of beans (about the same amount of energy when biting into a crusty bacon sarnie) again a couple of flashes on the ESP and it was away accelerating nicely.

After doing a few lazy turns in the car park to judge basic grip (quite good) I then set off to work. Snow was melting on main roads but around the edges still very snowy and slushy.

I managed to drive comfortably and without any drama at a good 10MPH faster than anyone else. Was able to overtake on dual carriageways where the outside line still had untouched albeit uncompacted snow.

Now if you even think snow tyres are an excuse to hoon around then you will learn the hard way (and hopefully your pride will be the only thing hurt).

Yes they give you grip and confidence but you must never let that confidence get the better of you. The tyres are not going to save you if you do something stupid or the situation catches you unawares (I imagine ice would be an issue). At all times I was in full control and driving cautiously(ish)

Only test yet to do is in heavy/standing water to see if it aquaplanes.

p.s. 300BHP RWD V8 not ideal platform for snow use testing

 

[whitenemesis]

I have the same tyres as the OP, same size fronts with 245/40/17 rears and would echo the findings here except the salted greasy surface comment. I have found the grip superior to my summer tyres (Pilot Primacy 2yrs ago and Falkens last year).

It does feel a bit like driving on jelly to begin with but the grip is there.

As moonloops says, winter tyres will not suddenly give summer day grip levels, so still needs great care!

With only just over have the power of moonloops chariot mine is perhaps a more gentle test

 

[moonloops]

except the salted greasy surface comment. I have found the grip superior to my summer tyres

I will do a bit more experimentation, I generally get a floaty sensation on greasy roads and you know the car is sliding about. Tyres have not done many miles yet so I may not be getting the best out of them. you never know there could have been diesel on the road when I had a bit of a slide !

 

[Shude]

Nice write-up!

It should be noted that it's tricky to compare brand new tyres of any type (first few miles you're still wearing the release agent off) with worn tyres (may have no grip left anyway).

 

[Bobby Dazzler]

Great summary.

My local tyre fitter suggested these KW27s too, but I opted for Michelin Alpins in the same fitment.

Today is the first day we've really had snow on the ground at home - about an inch. Last year in the same conditions I exited my driveway in a a barely controlled mix of slliding and wheel spinning. Today I just drove as normal (but cautiously).

The tyres seemed to come alive today. Impressed.

 

[raymont]

Here is a link to a German winter tyre test which includes the Kumho tyres:

Acht Winterreifen der Größe 225/45 R17 V im Test | sport auto

The Kumho tyres came 7th out of 8 and were conditionally recommended.

There follows the Kumho score sheet. Numbers in brackets are max score in category

Kumho I‘ZEN KW 27

Schnee (Snow)

Handling (30) 25
Fahrverhalten (20) (Roadholding) 18
Traktion (20) (Grip) 6
Bremsen (30) (Braking) 18
Summe (100) (altogether) l 67

Nass (wet)

Handling (30) 23
Fahrverhalten (20) 15
Lenkpräzision (20) (Steering precision) 15
Bremsen (20) 10
Aquaplaning längs (10) 8
Summe (100) 71

Trocken (Dry)

Handling (20) 19
Fahrverhalten (20) 16
Lenkpräzision (10) 5
Bremsen (20) 13
Summe (70) 53

Gesamtsumme (270) 191 (Overall score)


Car used SLK350.

 

[Shude]

Here is a link to a German winter tyre test which includes the Kumho tyres:

Acht Winterreifen der Größe 225/45 R17 V im Test | sport auto

I'm pleased to see the ones I've just bought are at the number 1 spot, although in fairness they were pretty-much the only ones left!

 

[whitenemesis]

Here is a link to a German winter tyre test which includes the Kumho tyres:

Acht Winterreifen der Größe 225/45 R17 V im Test | sport auto

The Kumho tyres came 7th out of 8 and were conditionally recommended.

There follows the Kumho score sheet. Numbers in brackets are max score in category

Kumho I‘ZEN KW 27

Schnee (Snow)

Handling (30) 25
Fahrverhalten (20) (Roadholding) 18
Traktion (20) (Grip) 6
Bremsen (30) (Braking) 18
Summe (100) (altogether) l 67

Nass (wet)

Handling (30) 23
Fahrverhalten (20) 15
Lenkpräzision (20) (Steering precision) 15
Bremsen (20) 10
Aquaplaning längs (10) 8
Summe (100) 71

Trocken (Dry)

Handling (20) 19
Fahrverhalten (20) 16
Lenkpräzision (10) 5
Bremsen (20) 13
Summe (70) 53

Gesamtsumme (270) 191 (Overall score)


Car used SLK350.

Curious how the traction is so low yet the handling and braking quite high?

I'd certainly agree with the steering precision in the dry (5). Turn-in is a little vague

 

[Satch]

There is most definitely a "break in" period for winter tyres. Yes you need to wear off the release agents and get some surface roughness, but modern ones work as "friction" tyres and get a lot of their grip from the way the sipes allow the tread blocks to conform to the road surface and siphon off the water. The sipes need some use to open up a bit.

Recall seeing a graph somewhere of winter tyre tread depth versus grip(which I cannot find now of course) that looked a bit odd to start with: the grip level went up from new (8mm) and peaked after a little bit of initial wear (7.8 to 7.5mm IIRC) before it started tailing off with decreasing tread depth as you would expect.

 

[S60_alex]

I recently had Continental Winter Contact 830s fitted to my Volvo S60 (FWD, winter tyre size 205/55/16 against summer tyres on 225/45/17).

I drove up from London to Edinburgh for a three day holiday on Saturday, getting back last night.

All I can say is - I am a total convert. I experienced cold dry and dry roads, slush and snow - from icy 1/2" thick polished snow to 12" deep powder.

Last year I drove my SLK on Michelin Pilot Sport 2's - this got stuck trying to get out of its own parking space on the flat, so was left at home. The Volvo (also on PS2's) was better, but useless and dangerous to be out in.

On the winter tyres, it was incredible. They're absolutely not wonder tyres that never slip or that can grip on sheet ice, but what they do give is a controllable level of grip, whereas with the PS2s I felt that I had very little feedback through the controls.

We were staying at the Dalhousie Castle (Luxury Castle Hotels In Scotland Near Edinburgh Midlothian : Dalhousie Castle Hotel) and were the only guests to make it out of the steep access drive on Monday - there were a number of other cars stuck at the bottom of the hill.

My main issue was ground clearance as the snow was up past the hubs!

I appreciate that deep snow driving is very unusual but for me the greatest benefit was (in stark contrast to the OP...) their performance on wet gritted roads (such as the northern stretch of the M6) where their performance was light years ahead of the summer tyres.

I have some video to show me driving up a hill in the snow (that I made my poor wife film in the -5 temps) that I'll post when I am home.

Alex

 

[Bobby Dazzler]

My Michelin Pilot Alpins came in 8 of 8 which is not great, but suspect that it's because they're compromise between winter tyre and performance tyre (V-rated). So far so good though.

 

[raymont]

My Michelin Pilot Alpins came in 8 of 8 which is not great, but suspect that it's because they're compromise between winter tyre and performance tyre (V-rated). So far so good though.

I'm afraid the test was a group of 'sporty' winter tyres. They're all V rated.

 

[Bobby Dazzler]

Hmmm. Even worse then.

 

[raymont]

Hmmm. Even worse then.

It's a pain in the UK as there is very little knowledge of winter tyres about, let alone comparative experience.

Tyre dealers (although there must be exceptions, perhaps in Scotland) seem to know nothing and / or just recommend what they can source.

Buying them without data is a lottery.

Having said that, even the worst of the winter tyres will be streets ahead of summer tyres.

 

[Shude]

Having said that, even the worst of the winter tyres will be streets ahead of summer tyres.

From what I've learned from reading over the last few weeks a new set of budget winter tyres will be great (if worn down quickly) in winter and rubbish in other seasons. Still better than part-worn summer tyres.

 

[clk270]

To the OP, as Shude already said, winter tyres can take 300-500 miles to wear in.

In these cold temps its also not so easy to temperature cycle the tyres unless you do a good high speed run. I had the benefit of switching to my winters a few weeks ago when the temperatures were around 3-12'C.

 

[moonloops]

To the OP, as Shude already said, winter tyres can take 300-500 miles to wear in.

In these cold temps its also not so easy to temperature cycle the tyres unless you do a good high speed run. I had the benefit of switching to my winters a few weeks ago when the temperatures were around 3-12'C.

I have done maybe 50 miles tops on them

 

[fuzzer]

Just had Dunlop M3 Runflat winter tyres and steel wheels fitted to the 320d by the BMW dealer who kindly store them and change them over for your from the summer tyres.

On in October and off in March is what they say.

AMAZING! stopping power on snow and ice is out of this world. Stops dead. Not a hint of traction control and ive been up very steep hills round about where i live that were untreated and brilliant.

Everything in its place but the bridgestone RE050's are great in the summer but my car was going sideways the last week. I can't believe its the same car. Feels like a 4x4 now!

 

[312 Sprinter]

Recall seeing a graph somewhere of winter tyre tread depth versus grip(which I cannot find now of course) that looked a bit odd to start with: the grip level went up from new (8mm) and peaked after a little bit of initial wear (7.8 to 7.5mm IIRC) before it started tailing off with decreasing tread depth as you would expect.

It's a pain in the UK as there is very little knowledge of winter tyres about, let alone comparative experience.

Tyre dealers (although there must be exceptions, perhaps in Scotland) seem to know nothing and / or just recommend what they can source.

Buying them without data is a lottery.

Having said that, even the worst of the winter tyres will be streets ahead of summer tyres.

If you read German there are a lot of comparison tests by ADAC and the like. They are worth wading through.

I use Vredestein SnowTrac 2 tyres on my Volvo. Chosen initially because the came out well in an ADAC test and they were the highest speed rating I could find at the time. About 2 weeks ago I threw on the same set I used last winter. I ran them too long this year, I'd lent my summer tyres to a friend to get his wheels reconditioned and I ran the winter tyres until early May. Consequently they were perfectly legal but down to 4mm or so, if not 3.5mm.

At that point they still work surprisingly well. Last Sunday I towed a loaded car trailer up a snow covered unmade roads leading to a farm. It romped up the hill without breaking into sweat.

This morning we had snow. My office and workshop are down a single track road and the turn is in a 90 degree bend. I turned into it this morning and I could feel the front end sliding sideways. I knew the tyres I had on were no longer optimal but it really didn't feel good. As I was turning a car coming through the bend flew straight into the ditch missing me by centimetres. Had I been 3 seconds later he would have landed in my door not the ditch.

I actually had another set of the right size tyres on Audi rims. I thought I'd better put on the better set of tyres. I failed to get/order new ones in time. I collected the Audi rims, threw them in the car and went to get the tyres swapped. By the time I drove past the turn going the other way, not 30 minutes later, there was another car in the ditch.

I replaced the low but legal tyres with an identical set of Snow Trac 2s with 7.5mm or so of tread. I turned into the same turn, it is lightly used and never gritted, and the car turned straight in.

The moral of the story is that winter tyres aren't really winter tyres at much below 4.5mm of tread. Be very wary of all the ebay offers of used tyres. Most seem to be at the 4 to 5mm mark. They are all but worn out. They really feel drastically better at 7.5mm than at 4mm!

This isn't as bad as it sounds BTW. As far as I can figure 2 of the tyres I dumped this morning had taken 60K miles to get down to a bit under 4mm.

 

[raymont]

If you read German there are a lot of comparison tests by ADAC and the like. They are worth wading through.

....... that's why I posted a link to a German magazine winter tyre test earlier in this thread.......