Why Winter Tires?
A new draft bill presented on December 8, 2017 at the National Assembly is seeking to advance the date when a vehicle owner is legally required to equip his vehicle with winter tires, i.e. from December 15 to December 1. The current law makes it mandatory for all vehicles licensed in Quebec to be equipped with winter tires from December 15 to March 15. But why is it important to switch over to winter tires? What are the differences between a summer tire and a winter tire?
Optimized Grip and Handling in Winter
It is generally acknowledged that it is necessary to change over to a different type of tire in winter, but most people cannot really explain why this is best for their vehicle and how winter tires really go about improving safety.
Let’s begin with the simple fact that when the temperature drops below 7 degrees Celsius a summer tire loses traction, which translates in longer braking distances.
Why does this happen? Summer tires become rigid at low temperatures since they are manufactured with a harder rubber compound and contain less natural rubber. There is a molecule in natural rubber that helps to keep tires supple in winter temperatures.
So it is the need to maintain this elasticity that explains why the percentage of natural rubber is greater in winter tires. This is important since a supple tire grips the road much better.
Even four season tires are not up to the task during Quebec wintry weather. Like summer tires, below 7 degrees Celsius, four season tires harden significantly and so lose traction. This is not the case with winter tires that offer greater handling, an enhanced adherence and shorter braking distances on new or packed snow, icy roads or on wet pavement.
Adapting to Wintry Conditions
To summarize, winter tires are highly recommended quite simply because they are manufactured with a gum compound that is better adapted to wintry conditions and allows for a more effective warm up of the tire at lower temperatures. While summer tires soften in the heat to offer better grip, in winter the opposite occurs: the tire hardens! Winter tires however maintain their elasticity, even in extreme cold conditions.
You may have noticed that winter tires do not have the same tread design as summer tires and have a greater number of sipes on the tread surface. The sipes grip the snow and ice to optimize tire performance. What’s more, winter tire tread patterns provide a space in which snow is compacted, which maximizes traction. Surprisingly, packed snow in the tread actually improves a tire’s grip on a road surface.
Besides the above mentioned characteristics, winter tires have ten times more sipes (small grooves on the tread surface) to better evacuate water and slush and ensure a permanent contact with the road. So beyond offering an enhanced traction and superior handling when cornering, winter tires go a long way in reducing the risk of skidding or aquaplaning. In short, the sipes and the progressive tread pattern of winter tires work together to evacuate water and slush, while gripping the snow more effectively for a better traction on the road.
Improved Performance and Savings In the Long Run
If you thought winter tires were just a gimmick, think again. Their performance has been scientifically measured. A car equipped with summer tires will have its braking distance multiplied two-fold on a wet road compared to the braking distance on dry pavement. And this braking distance is lengthened even more on a snow-covered road surface (braking distance multiplied by 4) and on ice (braking distance multiplied by 8).
Not only will winter tires keep you safer, they will have you save money in the long run. Summer tires wear faster on the icy roads in winter while winter tires become too soft in summer and so also wear more rapidly. Not to mention that braking distances are lengthened when running on winter tires in summer. Even if keeping your winter tires in summer is not illegal, you are still putting your safety and the safety of others at risk. Not to mention the wear acceleration of your winter tires. By alternating between winter tires and summer tires, the life expectancy of your tires can reach 90,000 km, i.e. some six years of use.
To learn more about which winter tire is best adapted to your vehicle, talk with your Point-S expert !