Due to the fact that the winters in central Europe are fairly mild, and because there are so many electronic aids (e.g., ABS), a great deal of car drivers think that they can do without winter tyres. Thereby, also the
electronics are dependent on a good contact between tyre and road. In the event of an accident, one can be held partly responsible, even though not directly having caused the accident, one can still be fined. Nowadays,
one can also be fined for driving on icy, or snow-covered roads with summer tyres. Some people - also public transport services - try to manage with "all-year-round tyres", this unfortunately, is only a compromise.
|Wide-wheels with comparatively little contact area|
When speaking of winter-tyres (those with the snowflake symbol), one used to assume, a large negative tread and a strong cross-tread. Nowadays this has changed. Negative treads (all the cuttings in the tread-
surface) can also be found, for reasons of aquaplaning, in summer tyres. Indeed, somewhat fewer across the tyre, therefore, more lengthwise. The wider the tyre is, the more negative tread it has, up to a surface area of
over 20%. It would appear, that the contact area of narrow- and of wide tyres is about the same. This also, because the, mostly smaller cross-section ratio, resulting in a harder side-wall, is shorter.
|Different rubber compound, fine- and chunky tread|
Winter tyres distinguish themselves by having a different rubber compound and higher portions of silicates and natural rubber. They make the tyre softer and they create, in contrast to summer tyres, also at lower
temperatures, decent grip. This is why winter tyres, when used in summer, wear out so quickly. Almost more important are the small, fin-like cross-grooves which can open and close themselves and are as deep as
possible across the entire width of the tyre. Through their changeability, snow cannot stick in them to clog up the tread. There is, with sinking temperatures, a turning point when winter tyres are superior to summer
tyres, also on dry roads. On snow, the winter tyre, at a speed of about 50 km/h, has a braking distance of about half that of the summer tyre. Nonetheless, one should not overestimate the traction potential by taking
|Winter tyres almost more important for four-wheel drive vehicles|
With winter tyres one can do without that last, little bit of top speed. Suitable winter tyres lose some of their good properties when pushed too hard in the direction of maximum speed. One should use the chance, with a
suitable sticker on the speedometer, (M+S-tyres), to enjoy driving a little slower than flat-out. Winter tyres are especially important for four-wheel drive vehicles, since here, when pulling off, the tyres lead one to believe
that one has great traction, when braking however, they have much less. Even worse is, because the four-wheel drive increases the weight of the vehicle, it's braking qualities which are, as a rule, not that good anyway,
get even worse.
|Only to a tread-depth of min. 4 mm, maximum 10 years old|
The minimum tread depth of 4 mm is not only valid when accessing the Alpine passes. Once they have too little tread, they should be replaced, they are not suitable for summer use because at high temperatures the
handling characteristics worsen. Of course, winter tyres only on the driven axle is not sensible at all, think of the steerability and the safety in curves. By the way, there are already tyre companies who guarantee the
qualities of their winter tyres for a period of 10 years. Don't however, calculate from the date of purchase, but from the four-digit DOT-number (week, year).