Feature Article: Siping Strides
Michelin’s Chris Tolbert says factory sipes are superior. “The angle, width and depth are certainly much more precise when originally molded into the tire. Michelin does not recommend aftermarket siping, but rather selecting the appropriate tread for the intended use or application.”
Roger Stansbie, Continental’s director of truck tire technology for the Americas, says, “We try to minimize sipes, especially in tires used in construction, because of stone drilling. Stones that get caught in sipes don’t come back out.” In this case, chunking can result. “Fewer are better. And, if the tire is damaged, it becomes the customer’s problem.”
Dan Guiney, director of technical service at Yokohama Tire, says, “You reduce the tread life with aftermarket siping. You increase flexibility when-ever you add a void.” He says you maximize tire life by keeping tread blocks from moving.
Walt Weller of CMA says, “My advice would be that, if you feel you have to sipe the tire, move it into another position where you need less traction; for example, moving a drive tire to the trailer.” He adds that excessive siping can make the tread “too squirmy.”
Thank you, Mr. Sipe
Siping was patented in 1923 by John F. Sipe, says William Estupinan of GITI Tires.
“Mr. Sipe worked in a slaughterhouse and grew tired of slipping on the wet floors,” he says. “He found that cutting slits in the tread on the bottoms of his shoes provided better traction than the uncut tread.”
The process was not applied to vehicle tires on a large scale until the 1950s, when superior tread compounds were developed that could stand up to the siping process.
Double Coin Tires’ Walt Weller says tire siping was later patented for use on tires by Goodyear. Truck fleets started copying the idea, applying it to tires in the shop for better wet road traction.