Tire Soak - To Soak Or Not To Soak, That Is The Question Photo Gallery
A hard tire does not adhere well to a rough surface because the contact patch does not conform to all of the surface area. The total square inches of rubber that meets the track is reduced when the tire is harder. By treating the tires, the surface is changed chemically so that it is more compliant and "fills" the areas around the high spots in the track surface. A treated tire would not benefit performance nearly as much if the track were smooth.