SEATTLE—Despite the calendar indicating spring had finally sprung, it had snowed like crazy on the lofty peaks and lower extremities of Mount Rainier. And that made the BFGoodrich folks very happy. Either they were in cohoots with the weather gods, or their timing was impeccable. Whatever the case, Michelin North America Inc.'s recent ride-and-drive introduction of the final link in its BFGoodrich g-Force tire family provided, in one day, a three-season opportunity to test the all-weather capabilities of the new ultra-high-performance T/A KDWS.
Touting the g-Force T/AKDWS as the ultimate tire "for those who enjoy driving their sports coupes and sedans in all types of weather," Michelin officials assembled a fleet that included a BMW Z3, Porsche Boxter, Mustang GT and Porsche Carrera. They then turned tire and automotive trade press journalists loose, first on the mountain, where most of the national park surrounding Rainier was closed to traffic due to an early morning snow storm.
The few miles open to vehicles afforded drivers a chance to slip-slide through several hairpin turns and unseen patches of "black ice" that would have proven tractionally challenging for even the mightiest winter tire.
Then it was off to Seattle International Raceway to see whether the new tire "delivers outstanding traction and handling in dry, wet and snow conditions," as Michelin claimed. At least for a couple hours the threatening skies held off, allowing journalist/drivers and their racing school co-pilots to maneuver a dry track before a deluge reminded everyone that, after all, this was Seattle.
Michelin's Rick Shafer, marketing manager, BFGoodrich brand passenger performance tires, explained that in 1998 the tire maker launched its g-Force T/AR1 racing tire for the SCCA Trans-Am series, replacing the Comp T/A racing version. Then several months later it introduced the g-Force T/AKD—the "D" is for drive—as a street tire with performance comparable to the R1.
The company's T/AKDWS—which stands for "dry, wet, snow"—replaces the BFG Comp T/A ZR4. It provides "breakthrough improvements in wet handling, substantial advances in wet braking and wet lateral grip, and improved handling, traction and progressivity in dry conditions," Michelin claims, as well as a quieter ride while still maintaining the ZR4's "impressive handling characteristics in the snow."
The tire's performance is attributed, in part, to its asymmetric tread design, though Mr. Shafer noted that it is non-directional, so the KDWS can be rotated. It features a center rib with tapered lateral voids to provide "excellent on-center feel, superb steering response and exceptional high-speed stability," the company said.
A patented S-shaped variable groove taper, combined with large, stable tread elements and multiple lateral grooves, enhances snow traction and, Michelin said, equalizes grip in wet and dry conditions. The S-groove, Mr. Shafer added, "can move almost as much water evacuation as a straight groove, except it provides much greater dry handling."
BFG officials painted a picture of an ultra-high-performance tire that is more than just a good all-season tire because, they maintain, it has few, if any, compromises over its seasonal range. Compared with the old ZR4's 300 treadwear grade, the KDWS carries a 400—the highest achieved by an ultra-HP tire, according to Michelin.
Mr. Shafer said the KDWS, which currently comes in 16- and 17-inch sizes, should eliminate the need for a driver to change from ultra-HP tires for the summer to winter tires.
Depending on how aggressively the tires are driven, drivers can expect a mileage range perhaps reaching 45,000 on the high end.
Using a new carbon-black-and-silica tread compound to enhance grip throughout a wide temperature range, the KDWS features two high-end-count steel belts in the crown area to promote very high cornering capabilities in dry conditions and help maintain cornering stiffness under high vertical loads, the company said.
Carrying a Z rating for speeds up to 186 mph, the new tire covers aspect ratios of 55, 50, 45 and 40.
The KDWS became available to dealers April 17. Mr. Shafer estimated the tire's average retail price will be in the $160 range, with a suggested base price of about $256 for a 285/40ZR17. However, he noted: "We don't set the price—but we are very competitive in the marketplace."