The Ultimate Guide to Tiresby Benjamin Yong | BCAA Magazine, Fall 2018
Most of us rely on tires every day of our lives. Yet we understand surprisingly little about these rolling pieces of rubber that separate rim from road. Sure, we know to keep them filled with air and fix them when they’re flat – but confusion abounds about the different types, terminology and traits, from rubber composition and tread patterns to performance. We spoke to industry experts for a deep dive on the topic of tires.
Tire types explained
We spoke to Steve Carpino, Senior Consultant on Product Design and Development for Pirelli Tire North America, about the main categories of tire available to BC consumers:
Formulated for a balance of attributes like comfort, noise and traction in wet, dry and light-snow conditions, all-seasons usually come with a high tread-wear rating, meaning excellent longevity. A better name would be “three-season tires,” however, as their rubber hardens and loses grip below 7°C.
Created with softer rubber that maintains grip in temperatures below 7°C, winter tires boast a level of cold-weather traction superior to all other types. The three-peak mountain symbol (see above) on the sidewall means the tire has passed a government-regulated test for traction on medium-packed snow. Some winter tires come with metal studs that dig into ice, although there are laws governing when and where you can use them (in BC, tires with studs up to two millimetres are allowed on highways October 1 to April 30).
Mud and snow tires:
A variety of all-season tire (identifiable by the “M+S” designation on the sidewall), these are designed with blockier and deeper grooves for evacuating mud and snow. As well, extra siping, or small cuts across the tread four to seven millimetres deep, open to bite the road surface (see the diagram on p. 20).
“Think of these as all-seasons with a focus on the more extreme winter conditions of snow, ice and low temperatures,” says Carpino. These are an option for drivers in frigid climates who want a year-round tire, as the rubber compound is designed to stay flexible above and below 7°C. Yet they can’t provide the same level of cold-weather performance as true winter tires, and they typically wear more quickly in warm weather than traditional all-seasons.
Sometimes known as summer tires, these are usually found on sport- or premium-segment vehicles. They’re capable of travelling at high speeds and designed to yield a high level of steering response and wet-dry traction. “The improved steering response may give a slightly harsher [or bumpier] ride compared to the all-season range of tires,” says Carpino.
BCAA Members get up to 25 CAA Dollars back with the purchase of four Pirelli-brand tires.
Don’t mix and match
Whatever type of tire you purchase, installing four of the same kind is essential to balanced braking and steering performance, says Carpino. “For example, if the wet-traction performance of tire A and B were significantly different, there could be very different reactions to braking and steering on the front and rear of the vehicle. This could lead to an unstable vehicle response in emergency situations,” he says.
Choosing the right set
Consider the following when shopping for tires:
Ride comfort: For the smoothest ride, look for “touring” models, suggests Barry Yutronkie, Director of Operations at the Tire and Rubber Association of Canada. These have a slightly higher aspect ratio, or sidewall height (how thick the tire is between the rim and the ground) compared to tire width. “A touring tire is usually a 60 or 65 series, which flexes more, soaking up bumps,” he says. “A 30, 40 or 50 series tire is going to be stiffer but more responsive, as the sidewall is a little shorter.”
Warranty: Most tires come with a manufacturer’s warranty covering defects, and a pro-rated mileage warranty, linked to expected tread life. Some dealers also offer road-hazard warranties, to protect against unexpected damage from things like nail punctures and potholes.
Longevity: Expect a trade-off between performance and life expectancy. Most all-seasons are rated for normal street and highway speeds, and designed to wear slowly, unlike tires rated for higher speeds. “You can’t expect a high performance tire on a Corvette to last 100,000 kilometres. That’s not what those tires are made to do,” says Yutronkie.
Caring for your tires
First and foremost: make sure your tires are always pumped to the correct psi, as indicated on the car’s driver-side doorjamb, says Stu Miller, Senior Operations Manager with BCAA Auto Service Centres. This helps with everything from ride quality to preventing accidental punctures. It also optimizes fuel economy, because driving on a tire that isn’t fully inflated expends extra energy. Regular tire rotation is also key to preventing early wear and other adverse symptoms – he recommends doing this every 10,000 to 12,000 kilometres.
It’s easy to monitor the health of your tread using tires’ built-in wear bars, notes Miller (turn the page to see a diagram).
“Wear bars are designed to be a visual indicator to tell you when the tires are worn out,” says Miller.
“When the top of the tread is even with what looks like a little speed bump in-between the tread pattern, the tires are essentially worn out.” And even if the treads look fine, have your tires checked annually by a professional, because rubber can degrade over time.
“You run the risk of popping the tire, and it’s also more prone to picking up nails or debris that could pierce through,” says Miller. “There’s also a loss of traction, since there are fewer grooves and less siping remaining. That could seriously impair your ability to control your vehicle in an emergency situation.”
Whether you’re sipping craft beer in Nelson or tasting BC wine in Vernon, plan ahead for a safe ride.
It's all in the Rubber
How do tires designed for colder applications stay supple under 7°C? The answer lies in their higher natural rubber content. Sport- and warm-weather tires contain a larger concentration of synthetic rubber, which handles heat well and actually performs better when warmed up.
Photo credits: iStock, Getty Images