New Michelin Tire Holds Wet Grip as It Wears

A new passenger car tire developed by Michelin & Cie. features a tread design and unique rubber compound that retains wet grip performance as the tire wears.

The Premier A/S tire's so-called EverGrip system consists of three elements: a high-grip rubber compound, rain groves shaped to widen as they wear and a set of hidden radial groves in the tire's shoulder that emerge as the tread become worn.

The tire's proprietary rubber compound contains sunflower oil and unusually large amounts of silica. The silica enhances road grip under wet conditions, and the sunflower oil improves wet traction at relatively cool road surface temperatures.

Conventional tires lose their ability to resist hydroplaning as they wear because their beveled grooves lose depth and width, thus reducing their ability to pump water away from the tread. Michelin says its EverGrip grooves get slightly wider as they abrade.

The tire also contains a series of tubular radial grooves buried in the shoulder tread. As the tire wears, the cross section of the tubes widens, creating wider grooves that give the tread more water-pumping capacity.

Michelin plans to introduce the Premier A/S series this spring in 32 sizes for a variety of passenger cars. The tire, which will be produced at five plants in North America, will come with a 60,000-mile warranty.