|MadSci Network: Engineering|
Watch out for snipers. What you were told about was siping, not sniping. Sipes are small slots that are cut or molded into a tire tread surface. On snow, ice, mud, and wet road surfaces, sipes usually increase traction. This name comes from John Sipe, who received a patent in the 1920's, after discovering that a series of small transverse cuts in the heels of his shoes gave him better traction. In a later US Patent to Goodyear, it was claimed that sipes improve tire traction characteristics as well. It also claimed that sipes tend to close completely in the tire 'footprint' on the road. Tire tread block shapes, groove configurations, and sipes affects tire noise pattern and traction characteristics. Typically, wide, straight grooves have a low noise level and good water removal. More lateral grooves usually increase traction. Sipes are small grooves that are cut across larger tread elements. Up to a point, more sipes give more traction in snow or mud. But, as is often the case, there are compromises. Winter tires, and 'mud and snow' tires generally have sipes, perhaps several thousand of them. They may feel 'squirmy' on a warm, dry road. Racing 'slicks' are used on dry roads to get maximum traction. These have no sipes, no grooves, and no tread blocks. They also have very poor traction on wet surfaces. Tire manufacturers use different tread rubber compounds and tread designs for different tires usages. If you already have tires that are best for dry roads, and you expect to do most of your driving on wet, muddy, and snowy roads, then siping your existing tire treads may be justified. You can find more information in following URL's on tires, tread design, and siping. www.dunloptire.com/glossary.html www.michelin.com/us/eng/tire/guide/terminology.html www.yokohamatire.com/04a3.html www.intlscience.com/TranslatorsCorner/TireTerminology.html
Try the links in the MadSci Library for more information on Engineering.