Tires: Where the Rubber Meets the Road
Without doubt, the most important — and by far the most ignored — safety component of any vehicle is its tires. Four contact patches, the surface areas where the tires are in contact with the pavement, control how well the car handles, stops and accelerates because they provide the sole traction for the vehicle. A great deal is expected from our tires and the vehicle’s well being — not to mention our own — depends upon how well they do their job.
Tire technology advances over the years have resulted in an immense range of characteristics that can be tailored to any vehicle or driver’s preferences. Tread design, rubber compounds, inner cord structure, tire profile (aspect ratio), speed, tread life and load rating all factor into how a tire can be designed for traction and braking in specific or varying weather conditions.
How the vehicle performs, rides, corners and brakes depends upon the choice of tire with which it is equipped. Designers and engineers work extensively with tire manufacturers to give each vehicle model the "feel" that is intended while maintaining safety and tread life.
Radial tires are the most prevalent on the road today, for a number of important reasons. In decades past most tires were Bias-belted. That is, the inner cords ran circumferentially around the tire and strengthening cord belts were laid at 45-degrees to each other, sharing both the surface under the tread and sidewalls. This resulted in sidewall flexing being transmitted to the tread and high rolling resistance, both of which made the tires less stable and more prone to "lane wander" and hydroplaning in wet conditions. Radial tires, by contrast, are constructed with the cord belts running 90 degrees to the circumference of the tire. More compliant sidewall flex allows the tire’s tread to stay in contact with the road surface, increases tread life and improves fuel consumption and handling. Thanks to the advent of the radial tire, a wide range of tire types available to the consumer offer an impressive number of qualities that should satisfy almost anyone.
There are a few rules of thumb that anyone contemplating a tire purchase should remember: