Winter tyre test -1000 miles report

Posted on January 8th, 2015 by Rob Marshall

report2I must admit to being rather late in equipping one of my cars with cold weather tyres, because this winter has been rather mild, to date. Since fitting a set of Continental ContiWinterContact TS850 covers to my 2.0-litre petrol estate car in November, we have experienced neither slush, nor snow. Many people are under the misapprehension that they are only suited to extreme conditions but their rubber compound is actually designed to provide maximum grip at temperatures below a notional seven degrees Celsius, in all weather conditions.

Bear in mind that my evaluation, as follows, was based on driving conditions that were not centred on frozen Finnish forests but in the wet wilds of the West Midlands. Therefore, the weather has been typically wintry, well, for the UK at least, being both cold and damp, but not always freezing.

Now that 1,000 miles have elapsed, what have I noticed? Or, rather, what have I not noticed? I have detected neither discernible increases in road noise, nor does the car seem to be any less reluctant to roll freely. As long-standing criticisms of cold weather tyres, I was seeking the signs, especially within the first few hundred miles of motoring.

Yet, fuel consumption has increased by approximately 10%, with 31mpg being recorded on the car’s on-board computer, as opposed to the 34mpg, indicated when all-season tyres were fitted. While I could blame some extra thirst on the tyres, I would have expected a similar drop being attributable to the chillier conditions (and extensive use of the heater and air-con to demist the glass) lengthening the engine’s warm-up time. Additionally, the local road conditions have been considerably wetter recently, compared to those of late summer and autumn. Wet roads, incidentally, increase rolling resistance considerably, as anybody knows, who has driven though a deep puddle at speed. Therefore, if the increase in fuel use is attributable to the tyres alone, I would have thought that it would have been negligible.

What have I noticed? Within the first 100 miles, I found that the car appeared to roll more over its tyres, under brisk cornering, and the tyres ‘felt’ softer and more compliant, compared to the all-weather covers that had been fitted previously. Yet, there was no lack of grip. Interestingly, the main difference was observed early in the day, on cold mornings. Turning out of my drive, onto a steep downward gradient, demands full steering lock and the passenger front wheel tends to ‘skip’ slightly under the stress. This characteristic disappeared, once the cold-weather tyres were fitted, suggesting that mechanical grip levels are quite high.

Wear rates tend to be faster, during the early part of a tyre’s life, and my front tyres exhibit similar wear patterns, after 1,000 miles of use. The inside treads of both covers have decreased by 0.1mm, on average, while the outer shoulders have lost 0.4mm. While the centre tread depth measured 8.9mm, when the tyres were new, they have now reduced to 8.3mm. I would expect this trend to continue, prior to the wear rate slowing. I should highlight that my car’s tracking had been optimised at the time of fitting.

I shall report on further findings, in 1,000 miles time.