* Winter versus summer tyres * Winter tyres perform better in cool, wet conditions too * Tests conducted in Sweden and Germany...
The first of our wet tests measured the braking distance of each tyre from 50mph. The temperature during the runs averaged 4C and the premium brands of winter tyre dominated. They stopped our Volkswagen Golf test car an average of four metres shorter than the premium summer tyres.
The budget winter tyre the Nankang SV-2 was off the pace, and was beaten by the Continental and Michelin summer tyres. It still stopped 2.7 metres shorter than the budget Nankang summer tyre, though.
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Aquaplaning happens when the tread of the tyre can no longer cope with the amount of water on the surface of the road, so a layer of water develops between the tyres contact patch and the asphalt. When a car aquaplanes, braking and steering inputs have no effect, so the driver loses virtually all control.
Our aquaplaning test consisted of accelerating along a special section of test track with 7mm of water on it. The greater the speed achieved by the tyre before it started to aquaplane, the better the tyre. Despite this test being carried out in northern Germany during early March, the average temperature was outside the ideal range for winter tyres a relatively balmy 11C.
This could explain why the summer tyres performed marginally better; the only winter tyre that beat its summer counterpart was the Goodyear. Overall, though, the results were neck and neck, with the average speed achieved by the summer tyres less than 1mph more than the average for the winter tyres.
We also used a special wet circuit to assess handling characteristics. Each tyre was scored out of 10 for grip, steering and traction out of corners.
The winter tyres took two of the top three positions, with generally better steering feedback. However, Continentals summer tyre the ContiPremiumContact2 surprisingly topped the score sheet in every area. This is possibly because the average temperature during this test was 5C, which is just within the temperature threshold recommended for winter tyres. Continental says in-house tests have shown its winter tyre outperforms its summer tyre below around 2C.