Monday 24 October 2011

The Importance of Wearing the Correct Rubber

After meaning to for some years (and ending up accumulating half a garage full of spare rims), I finally got around to buying and fitting a set of winter tyres last year. To allay any confusion you may have, dear reader, I don't mean tyres with steel studs in for dealing with Scandinavian ice, nor do I mean 'snow' tyres. I mean tyres of a 'rubber' compound designed to stay supple in cold and freezing temperatures, and with a deep tread pattern optimised for rain, snow and slush, and general UK winter beastliness. 

Generally, high performance tyres available in the UK are optimised for summer use, and once the temps drop to below ~7 degrees, the compound becomes hard, and unable to key into the road surface. And large, flat contact patches that give great grip on warm, dry tarmac are pretty useless if there's any snow on the ground. Which explains all that TV News footage of executives sliding out of control down the main road once an inch of snow hits the south east's rush hour.

It’s long been common practise in continental Europe to have two sets of tyres for one's motor. A nice set of alloys with low profile tyres for summer, and a set of old steelies and winter tyres that get fitted once the colder weather sets in. I believe that now tyres marked with a snowflake are even mandated by law in alpine German states from November to March.

For many years, this habit was a funny foreign one, and us Brits, protected from icy blasts by the benign warming seas surrounding our island, carried on regardless. Unscheduled trips into the ditch on winter's days were blamed on 'black ice', and we relied on the fitful and corrosive efforts of the council to spread salt on the roads, thereby preventing water from freezing (at least until it got to quite a few degrees below zero).

Several things have changed since those carefree days of yore. Firstly, we've all fallen victim to 'Ring fever - even humdrum hatchbacks have wide, low profile tyres, secondly a long string of mild winters mean there's a generation of drivers unused to managing in snow and ice,  and thirdly, the changing climate has hit us with a series of cold winters.

I remember arriving on the South Coast to live five years ago, and being told that it never snows here. It has every winter so far. In fact here's a picture of Aldwick beach in January 2009.


I now work freelance; if I don't turn up for work because it snowed, I don't get paid. So last November I bought a set of skinny 16" steel wheels from my local VW garage and after a bit of hassle, got Kwik Fit to mount a set of Continental winter tyres to the Golf.

There was a noticeable difference. The fatter sidewalls did take the edge off the Gti's harsh ride, and there was a drop in traction compared to the summer tyres. Full bore 2nd gear runs up a local hill produced more torque steer.  High speed straight-line stability also suffered a little. It was quite a compromise.

Then about three weeks later it snowed heavily while I was at work up near Gatwick airport. The industrial park is on the edge of town, and the ground falls away from it on three sides. I was one of the last to leave work, and heading back to the coast on my usual back roads route. I joined the main road at a hilly junction to find it in a state of complete chaos. Cars were all over the place, some trying to work their way up the hill on the grass, others with several men pushing, engines screaming, others pointing at haphazard angles up the hill. Behind all this was a long queue of stationary traffic. Lucking I was travelling against the flow. I turned onto the road, covered in several inched of packed snow, and just drove down the hill. It even felt quite normal; no spooky lightness through the steering.

So I hit the brakes to see how much grip was there. The car just stopped dead, as you'd expect it to do if there was simply rain on the surface. I drove happily home, running at 40-50mph on white roads, overtaking the odd hatchback crawling along, and a few 4x4s, whose driver's assumed the £60k they'd spent on their Range Rover/X5/Q7/M Class meant the laws of physics didn't apply to them. Until they found 2 or 3 tonnes of car sliding under them as the little red Golf sped past.

The snow cleared after a few days, but it was back again with a vengence over the Christmas break. In between Christmas and the New Year I had to travel up to the Thames Valley for a family lunch. With my two sons in the back happily occupied with PSP's I headed up the usual A and B road country route.

The roads that morning were deserted. The snow that had fallen a few days earlier was still on the ground, nights of frost had turned it into tracks of ice, with deep ruts of hard packed snow and slush where vehicle tyres had banked it up in-between lanes. The only other vehicles out were those same 4x4's, their drivers having now learnt that a 4x4 equipped with summer rubber may accelerate better than normal cars, but once you start braking they still only have the same braked four wheels.

I drove 75 miles in perfect safety, the only excitement caused by the flashing headlights of 4x4s I had the temerity to overtake.

In March I put the alloys back on for the summer, and the winter rubber went back in the garage. 

Again I noticed the back to back difference. I could feel the added unsprung weight, steering response was dulled, secondary ride deteriorated, and there was a significant amount more road noise.  But the upside is massively increased response to initial turn-in, mid-corner grip and traction. Straight-line stability is also much improved. In this way i enjoyed my summer's motoring.

The nights are drawing in, the first frosts have arrived in the downs, and it won't be long before I spend a Saturday afternoon re-fitting my steelies again.

SS7



4 comments:

Anonymous said...

What an adventure!

Anonymous said...

I agree, sounds like fun down in Bognor regions! :)

BestCarQuote said...

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Helen Grainger said...

Hah! I learned the hard way from purchasing cheap tyres online a few weeks ago. Never again. Next time I plan to be suited and booted for winter =)