Stay safe and mobile this winter by investing in cold-weather tyres
Published 13/11/2011 | 05:00
Seven degrees. That's the temperature, in degrees Celsius, at which your car's tyres become less effective. Forget the newsreel images of snow-covered roads and slip-sliding cars; winter is more than a week or two of chaos-causing cold white precipitation; it's a season that lasts more than a few days. Winter tyres aren't snow tyres; they're designed to grip, stop and turn better than a conventional 'summer' tyre when the temperature drops -- in the wet or the dry.
Darren Lindsey from Goodyear told the Sunday Independent: "More natural rubber in the tyres prevents hardening of the tyre and a corresponding drop in grip, traction and stability."
When the total area in contact with the road, spread over all four tyres, is only about the size of the palm of your hand, that's crucial. Cold-weather tyres also benefit from special tread patterns, with an increased groove ratio and up to 10 times more 'sipes' than a conventional tyre. The result is marked; TUV testing in Germany measured a winter tyre's stopping distance on snow from 50km/h to a standstill to be 32 metres. Compare that to a standard tyre's 63 metres -- almost double -- and it's clear that having the right tyres for the conditions makes sense.
Figures issued by the Climatology and Observations Division of Met Eireann underlined that December, January and February 2009/2010 saw mean air temperatures around two degrees lower than average for the 1961-1990 period and the coldest winter since 1961/62. Between 70 and 80 ground frosts were recorded, even though rain and snowfall were only half seasonal levels in some places.
Snow or not, the benefits of winter tyres are obvious. Don't think either that four-wheel drive is the answer -- if there's no grip, there's no grip, however many of your wheels are driven. First-hand experience of this on a snowy French alpine road in a Mitsubishi Pajero 4x4 underlined this for me. On regular tyres, with all the clever diff locks activated, the big off-roader slid gently backwards down a hill with all wheels spinning forwards. Locals, in their tatty old hatchbacks with only front-wheel drive and the correct tyres, passed with no trouble at all.
To move I resorted to snow chains, fitting them being something I wouldn't wish on my worst enemy. Snow socks with their zips and clips are much easier, and cheaper, but they're still a last resort option whereas a winter tyre will see you through a season.
Obviously there's a cost implication, but you'll likely buy at least one set of tyres for your car while it's in your ownership.
Buying a set of winter tyres offsets any wear on your standard tyres all the time they're not being used. Modern winter tyres have similar wear rates to standard tyres now too, while they can also be as fuel efficient and quiet.
Little wonder then that most of our European compatriots have legislation making cold-weather tyres mandatory during the winter months. If mobility is a necessity then the benefits of cold-weather tyres outweigh any cost or inconvenience factors, not least to mention the safety implications.
Keep an eye on that thermometer ...
Sunday Independent Supplement