Winter for motorists is not only snow and frost. It’s this age-old fuss – preparing car to unfavourable season. Your confidence on the snow-covered road and in icy conditions strongly depends on snow tyres. Of course you can use summer tyres in winter, but you will risk your own car and represent a danger to other participants of road traffic. At the same time different snow tyre models act differently in various conditions. It isn’t easy to choose one exact set of snow tyres. Often, you have to use your own experience and buy products that have made a good showing. Besides, the choice of snow tyres depends on the weather conditions in your region. That’s why we can’t say that some snow tyres are better then other. Though, we can give few common recommendations for snow tyres selection.
Studded or friction
It is not simple to say what tyres to buy - studded or friction. From theoretical point of view, studs on snow tyres should provide higher coefficient of wheel cohesion with road, which is especially important in the icy conditions. But sometimes snow tyres without studs act better on the slippery road then studded tyres. So what’s the point?
Car conduct on the road depends not only on the presence/absence of studs. Determining factors are also rubber chemistry and tread pattern.
Let’s try to examine, what is better in exact conditions?
Studded snow tyres
In icy conditions the cohesion coefficient is heightened with a help of studs.
There are two ways: either you buy studded tyres, or you stud your usual snow tyres. Of course the more there are studs, the better will act the car (braking distance decreases, the probability of thrashing is less). Studs shouldn’t be on one line, but chaotically spreaded on the tyre surface for higher effectiveness. But remember that not every tyre can be studded. Ask a shop-assistant about it.
Studded tyres that have showed themselves on the slippery road are Nokian Hakkapeliitta. Their peculiarity, starting from the forth model is square, but not round as in other tyres, section of studs. It provides better cohesion with the road.
Non-studded snow tyres
When you are driving in deep snow, car controllability depends not only on the presence of studs, but also on the tread pattern of snow tyres. Usually the most effective are snow tyres with majority of rectangular blocks, set in staggered order. The depth of the pattern is also important. In majority of models this parameter is from 9 to 10mm. Cohesion with the road is also effected by the presence of small strips (lamella) on the tread. They improve the cohesion of studded as well as non-studded tyres.
If the snow on your road is wet or there is no snow at all, then you should think about the purchase of non-studded snow tyres. First, studded tyres won’t be effective while accelerating and braking on asphalt road. Second, contact patch of the wheel and the road decreases. It leads to the decrease of cohesion coefficient and, as a result, car controllability is worse. Third, on the asphalt studded snow tyres will become an additional source of noise.
What should you know, selecting non-studded snow tyres.
On the wet snow better controllability of the car is gained by the tyres with directed tread pattern, which helps to lead the slush from under the wheels. The pattern of such snow tyres looks like in summer rain tyres, where the tread construction resembles herring-bone.
Continental ContiVikingContact3 are considered to be the best tyres among non-studded snow tyres. The price of these tyres depends on the type and size of the wheels.
General recommendations
Snow tyres are usually used for 2-4 seasons. When they wear out – the tread depth becomes 4mm or less – they should be changed.
Rubber-stock formula for snow tyres is selected in such a way, that the wheel “sticks” to the slippery surface. That’s why soft snow tyres are more appropriate for snowy and icy conditions. In winter soft tyres are also effective on the asphalt, but they are faster worn off – harder rubber is advised. It is difficult to check this factor by touch, but shop-assistant can advice you something exact.
Snow tyres with asymmetric tread pattern are often more effective. In such case, for example, outer part of the tyre is responsible for the driving on the asphalt and inner part – on snowy surface. You only have to mount such tyres due to the marks.
Snow tyres dimensions
Snow tyres dimensions (as well as summer tyres) should be selected among those that are recommended by producer. If you buy wider tyres, the contact patch will of course increase. But the car mass will be spreaded in such a way that the cohesion of tyre with road surface will decrease.
If there is no necessary size, then it is better to buy a little bit narrower snow tyre model, but with higher tread.
Snow tyres exploitation
Many people “shoe” their car in snow tyres only after the first snow. It often leads to the increase of car crashes in the beginning of winter. In general case it is recommended to change the tyres at the temperature of 7°C.
Snow tyres, studded as well as non-studded, require careful exploitation on first few hundred kilometers. Running in without quick braking, with smooth acceleration and careful turnings are recommended to save the quality of tyres for a long time. It will especially influence the studs in the tread.
A lot of people inquire, if it is possible to put snow tyres only on driving-wheels and to save money. It will of course influence the driving, but not always positively. Of course you will feel the positive difference when you take off, but there can be few negative surprises while driving. For example, in rear-wheel car the mass is transferred to front wheels while braking, as a result, the benefit of snow tyres on rear wheels is not so big. While turning on the icy road, a car with rear-wheel drive and studded tyres only on rear wheels, can’t be operated properly. Front-wheel cars also have this problem. Snow tyres only on front wheels allow to start off quickly. But while braking or even retarding speed, rear wheels will skid. That’s why, if you buy snow tyres, buy the full set of tyres. Of course if you drive carefully and not very fast, you may not feel any difference. But in unexpected situations (emergency braking, drift) your car will be better operated, if it has a set of identical snow tyres.
If you have bought studded snow tyres, but because of changeable weather you have to drive on the asphalt – you should be more careful. Quick take off or emergency braking are forbidden, if you don’t want to loose all the studs at once. Don’t forget to stick a special mark on your car, so that other drivers will know that you have a shorter braking distance and will keep larger distance.
In the conclusion, we would like to recommend you firms who make qualitative snow tyres. These firms are Nokian, Michelin, Continental, Pirelli, BridgeStone.
Make a good choice!