November is here, which generally means three things happen across our frozen nation: Tim Horton’s rolls out some winter-themed cups, everything is tinged with the flavour of pumpkin spice, and Canadians start talking about winter tires.
Regardless of how many axles are powered on your vehicle, winter tires are an important safety element of any vehicle plying Canadian snow-covered roads. Rubber compounds found in all-season and summer tires stiffen up once temperatures dip below 7 C. The physical construction of a winter tire is different, too. Winter tires set themselves apart from their fair-weather brethren both mechanically (tread design) and molecularly (rubber compound).
Try this experiment. Take a block of normal styrofoam and push it along the surface of your kitchen table. It slid pretty smoothly, right? Now, cut four or five shallow grooves in the styrofoam’s surface and try to push it along the table again.
Different, eh? The extra surfaces you made when cutting grooves in the styrofoam create more area for grip. In the tire industry, these grooves are called sipes.
Don’t just take our word for it, though. We went right to the top, speaking to Irene Aguzzi who works at Michelin, one of the world’s largest tire manufacturers. “The tread on winter tires are packed with sipes which furnish numerous edges which bite into the ice and snow,” explained Ms. Aguzzi. “The saw-tooth shaped edges on the tread blocks provide even more gripping surfaces, especially when compared to an all-season or summer tire.”
When shopping for winter rubber, look for the Alpine pictograph (a snowflake inside a mountain) on a tire’s sidewall. This mark says a particular tire passed the ‘medium-packed snow test’ designed by Transport Canada to simulate Canadian winter driving conditions.
Here are nine great winter tires designed to get you through the harshest Canadian winter driving conditions, presented in alphabetical order.
BFGoodrich Winter T/A KSI
This new tire from the boffins at BFGoodrich pack in an incredible number of sipes in order to furnish more edges with which the tire can bite into ice and snow. Sipes are all those little lines you see in the tread blocks of good winter tires … and the Winter T/A KSI has lots of them. The tread blocks themselves feature edges shaped like the teeth of a saw, providing superior grip.
Wide lateral grooves and a directional tread design sweep away slush and water, giving the tire a better chance of staying in contact with the driving surface. A high density silica compound allows the tire tread to be flexible at sub-zero temperatures, delivering great traction, but then firm up a bit on warmer winter days to improve the tire’s durability.
The Blizzak line of tires arrived in Canada twenty years ago as an option for drivers who sought winter grip without the harshness and noise of metal studs. Arguably, it was the first tire to feature a special rubber compound, which dramatically improved all measures of performance on ice-covered surfaces.
Built with thousands of microscopic tubes and cells (which actually resemble the consistency of Swiss cheese when examined through a microscope), the Blizzak tread wicks away water which often forms between the tire’s contact patch and the surface of snow-packed and icy roads. This creates a sticky bond with the road surface, like the feet of a gecko. Blizzaks are now available in a wide variety of sizes for passenger cars, light trucks, and even performance vehicles.
Continental WinterContact SI
Packing Continental’s Polar+ technology, this studless winter tire is specially designed for family vehicles like passenger cars and crossovers. Jagged traction grooves in the tread blocks offer additional biting surfaces, improving grip in the snow. At the base of these grooves are additional edges that provide even more snow-biting surface to improve braking and handling traction. The staggered positioning of the tread blocks allow for a more consistent contact patch with the ground.
Large channels in the tread pump water and slush from the tire’s contact patch, helping keep your tires in contact with the pavement and your vehicle out of the ditch. The WinterContact SI is available in a wide range of sizes, from rim diameters of 15-inches to gonzo 20-inch hoops.
General Tire Altimax Arctic
This high-value tire incorporates the company’s Quad-Tech technology, said to combine the strengths of multi-angle sipes, a directional pattern, special silica composite construction, and tread blocks which react to the driving surface. Combined, these four pieces of the winter tire puzzle offer great traction and good handling characteristics when compared to squishy winter socks of the past.
Available in a host of sizes all the way from economy car 13-inch tires to popular 17-inch rubber, this tire is pinned for winter studs should a customer choose to add them. General’s placing of the stud jackets is optimized for added grip on ice.
The iPike family of winter tires is offered in several styles from the studdable workaday W409 to the performance-focused W149. Its aqua-slant technology provides efficient water evacuation over puddles and slushy roads, maximizing one’s mechanical grip. New soft compound technology increases ice braking performance offering a much wider contact area than conventional tires, which also improves wear and ice traction.
Kerfs are small slits in a solid surface, and Hankook takes great care to point out that the number of kerfs in their iPike winter tires go a long way to enhancing grip on icy or snowy roads. A light-truck version of this tire is available as well.
Kumho Wintercraft WP71
There are three different tires in the Wintercraft line but the WP71 stands out as the high-performance offering. Showcasing a contour design that provides significant enhancements to wet performance, it also does well for itself in dry handling and treadwear measures. The WP71 features a uniform block design that delivers great grip and stable cornering.
The application of honeycomb-style 3D sipes maximize interlocking between tread blocks, creating extra surfaces on the tire for improved traction on snowy and icy roads. Live somewhere that experiences deep snow conditions? Be sure to check out one of the other two tires from the Wintercraft line.
Michelin X-Ice Xi3
The Michelin X-Ice Xi3 is a studless ice & snow tire designed to deliver superior snow and ice traction. Now in its third-generation, the X-Ice name puts a lot of emphasis on the longevity of this tire, a common complaint levelled at winter tires given their softer rubber compound which lends itself to wearing out more quickly when compared to a traditional all-season tire.
Cross-Z sipes, so named for their zig-zag pattern, do dual duty on the X-Ice. As with other tires, the sipes help clear out liquid from between the rubber and the road, increasing traction. Their unique shape, however, is designed to control shear stress, which reinforces each tread block, reducing wear and extending the life of the tire. The X-Ice also has a uniquely shaped contact patch to evenly distribute the forces of acceleration, braking, and cornering. Its directional tread design vacates water and slush, improving hydroplaning resistance by keeping the contact patch kissing terra firma.
Nokian Hakkapeliitta 8
In high-speed, off-road racing – especially of the winter variety – there is an old saying: “If you want to win, hire a Finn.” This said only half-jokingly, as Finnish drivers seem to have an uncanny ability to keep their cars shiny side up when the roads get slick. Safe to say, then, they know a thing or two about winter tires.
Nokian is a Finnish company which, true to form, operates a permanent winter tire testing facility where it develops and tests their winter rubber. Their Hakkapeliitta 8 is a studded tire, designed to provide phenomenal traction in foul weather. Nokian has figured out how to reduce the noise level of studded tires by developing a cushion which rests underneath the metal stud. This allows the stud to grip on snow and ice, yet absorb impacts on dry pavement. The uniquely designed centre section helps with steering response. It is also fun to say ‘Hakkapeliitta’ aloud.