Winter tyres
The nights are drawing in and cars are covered in a thick veil of mist of an evening. Winter is well on it's way, and as a motorist, now is the time to take action.

With two tough winters behind us, you will have seen and heard tyre and car manufacturers promoting the benefits of these tyres and why you should have them fitted.

But what are they and why should we buy them?

First things first, winter tyres are not just for use in snow. You may think that we don't need winter tyres because we only get a few days of snow a year. The truth is, though that winter tyres offer so much more than just a bit more traction in the white fluffy stuff.

A softer compound means winter tyres provide optimum performance under 7 degrees. Sipes (little slots in the tread) are designed to bite into the road. In contrast, summer tyres have a hard compound which stiffens up in low temperatures and dramatically reduces friction. Not what you want when you go to slam on the brake pedal.

Winter tyres offer fantastic grip in a variety of conditions including greasy, cold, wet and icy roads. They are in a different league during the colder months compared to normal summer tyres, which most cars are fitted with.

A study by the British Tyre Manufacturers' Association (BTMA) found that on wet roads, summer tyre increase the stopping distance from 62mph to rest by over five metres.

On icy roads, summer tyres take a further 11 metres to stop from just 20mph compared to winter tyres. That's well over two car lengths.

As a general rule, they should be fitted in early to mid November and changed for summer tyres in late February/ early March, although this is weather dependant. That's not to say that winter tyres cannot be kept on all year round. The road-holding abilities will still be very good, but the wear rate will be accelerated on warmer roads.

How much are they?

Many drivers feel that the cost of winter tyres is prohibitive. Yes, some premium brands can be very expensive based on the size of your rims (anywhere in the region from £40 for budget to £150 each for premium), but there's generally only a few pounds difference in buying winter tyres compared to summer tyres.

The average price of four winter tyres can cost up to £600 which is a lot, especially when you already have a set of black round things on the car and you're only going to use them for about four months. But think about it this way; if you lose grip in winter and have a prang, your insurance premium is only going one way. Even a small front end knock could cost up to £1000 to repair.

A cheaper option is available in the form of snow socks. Retailing at around £50, they are a shaped pad that fit over the whole tyre and gives you grip when you're really stuck in snow. Ideal to get you out of trouble, they are only suited to driving for a couple of miles at very low speeds - go over 30 mph and they will be ripped off the wheels.

All weather tyres are the middle ground between winter and summer tyres. They can be used all year round and provide adequate grip in summer but better traction in winter. However, winter tyres will outshine them as soon as the cold weather kicks in. You may find that all weather tyres will wear quicker, depending on mileage and driving style, and in my opinion they are not a patch on winter tyres. Still, this may be a better option if you don't want to fork out for two sets of rubber.

Can I fit them straight on?

Last week, Autocar found after an extensive report that it is NOT illegal to fit winter tyres to your car and they are not generally seen as a modification, unless you fit much more expensive wheels at the same time. Therefore, you can walk into your local tyre dealer and get them fitted while you wait.

Can I get away with just buying two winter tyres?

It seems simple; if you have a front wheel drive car, surely you only really need two winter tyres for the front wheels and vice versa for a RWD car, right?

Wrong. In fact, mixing tyres can be even more dangerous than just sticking with your summer rubber. Why? Well, this is because the different tread designs of the car do not work with each other. Often the two winter tyres will grip on while the two summer tyres simply skate on the water, ice or snow with little to no grip at all.

The videos below go some way in illustrating the shocking difference in winter and summer tyre performance. A very slippery epoxy surface demonstrated similar conditions to that of ice and snow. The cars were driven at 35kph downhill and through a corner.

As you can see, the winter tyres stick to the road and there's no drama. In the car, I felt confident in the cornering ability and it stuck to the road like glue. The car did suffer some understeer, but was responsive and easy to correct.

The summer tyres are a different story. The car understeered heavily and a dab of the brakes did nothing. It locked up and slid until we hit the dry tarmac.

Now for the mixed tyres...

Absolutely no traction was available at all. The two winter tyres on the front wheels of the Golf tried to grip and sent the back into a slide almost instantaneously. As the fronts kept scrabbling around for grip, the car went 180 degrees before the dry tarmac stopped it.

These are only simulated tests, but it shows that drivers who do mix their tyres could easily end up having a serious collision once the temperature drops.

We all have to adapt our driving habits during winter and ensure that our cars are properly maintained. One of the best ways to stay safe and drastically reduce the chances of having an accident over the coming weeks is to fit winter tyres. Sure, initially it's an expensive outlay at a time when we're all feeling the pinch, but compare them to your summer tyres on a wet or icy day, and they will soon make perfect sense.

Still not convinced? Well, I'm putting a set on my car and will be reguarly reporting how they fare in the real world on Autoblog in the coming weeks. Look out for my long term updates.