Why is it important to use winter tyres on snow or ice?

Why is it important to use winter tyres on snow or ice?

Snow and ice are the most challenging conditions drivers typically face and the tyres they use can make a big difference. New cars, vans and light trucks are usually fitted with either summer or allseason tyres as original equipment. They are not fitted with winter tyres. Summer tyres provide traction on dry, wet and warm conditions but they were never intended to encounter winter's cold slush, snow and ice. While all-season tyres provide traction in a wider range of temperatures, we found that they can be a jack of all trades and master of none. In order to better understand how much traction these types of tyres provide on the ice, we compared them to today's hi-tech winter tyres with our local ice rink's glare ice replicating the slippery intersections often encountered during winter.

We began with acceleration, comparing how long it took the test cars to cover a 60-foot distance to the centre of the ice rink. The summer tyres on the red car relied heavily on the traction control to begin their trip and took 7.4 seconds to cover the 60 feet. All season tyres on the silver car relied less on the traction control to initiate their trip down the ice, but still took about 6.5 seconds. The stud-less winter tyres on the blue car provided optimum grip on the ice, taking only about 21 feet 2 inches to stop. The stopping distances are most obvious when to compare the results side by side.

Our final test relied less on traction control and more on their ability to grip the ice. They took on about 4.5 seconds to complete their run. We evaluated stopping traction by measuring how many feet it took to come to a complete stop from ten miles an hour.

The limited ice traction on the summer tyres on the red car caused the car's anti-light breaking system to work over-time and they took about 47 feet to stop. While the all-season tyres on the silver car relied less on the car's ABS to control lockup. It took them about 39 feet and 10 inches to stop the vehicle. The stud-less winter tyres on the blue stop the stopping differences were most obvious when you compare the results cornering where we compared the cars marked by traffic cones.

Let’s look at the key difference between summer, winter and all-season tyres.

Summer tyres

Summer tyres are good for spring and hot season. These tyres have soft and shallower tread that provides grip on dry as well as the wet surface. They have fewer grooves for better traction and control on the road. These tyres have better braking capabilities and more hold on the road. These tyres are not meant for cold temperatures. If these tyres are used at freezing weather their rubber tends to harden and they lose their grip on the road.

Winter Tyres

Winter tyres are designed especially to deliver excellent performance during winter season and snowfall. They have softer and flexible tread rubber than summer tyres that remain soft in freezing weather and provide maximum grip on the snowy surface. These tyres have a deeper tread pattern and more grooves, so as to maintain traction on the snow. These tyres also have sipes, which are small rubber pockets that absorb water and release it from the back of the tyre while rotating.

All-Season tyres

All season tyres are designed to work all year long. These tyres are generally fitted in brand new cars. They are quite popular as they provide a good ride in dry, wet as well as mildly cold conditions.

Unlike summer and winter tyres, these tyres do not impose danger if used in alternate weather conditions. These tyres are less costly and provide good traction. Although one can use these tyres all year long they are not ideal for all situations. These tyres are best suited for moderate temperatures and can bear little heat as well as little cold but they should not be used during extreme dry, wet or cold conditions.

Construction of winter tyres Winter tyres are high-performance tyres which are specially designed to provide a firm grip while driving on snow, ice or wet surfaces in cold weather. These tyres must be equipped in the vehicle when the temperature constantly remains below 7 degree Celsius. Using summer tyres on snow increases the stopping distance and the vehicle needs a longer duration to come to standstill. Let’s now look into the details of how these are constructed.

Rubber Compound: Winter tyres are made up of extremely soft and highly flexible rubber compound so as to provide maximum grip on snow. Soft rubber is capable of holding and sticking to the ground firmly which enhances the grip. Unlike the usual tyres, the rubber compound in these tyres contains more ratio of natural rubber instead of synthetic rubber.

Tread Patters: Wide and deep tread patterns ensure proper dispersing of water to avoid the risk of aquaplaning. Tread depth of winter tyres makes them unique make compared to normal ones. 8 to 9mm of tread depth is considered appropriate and is the minimum requirement for these tyres. The presence of tiny grooves along with deeper tread holds the snow which provides more traction and helps smooth forward movement.