Adding circumferential grooves and sipes to oval track dirt tires can enhance traction by improving the tire's ability to grip the track surface. Here's how it works:
- Circumferential grooves: Circumferential grooves are long channels running around the tire tread's circumference. These grooves help evacuate water, mud, and loose dirt from the contact patch between the tire and the track. By channeling away the excess material, the grooves prevent the tire from hydroplaning or skimming on the surface, allowing the tire to maintain better contact and grip.
- Sipes: Sipes are small, thin slits or cuts in the tire's tread blocks. They can be placed in a variety of patterns, including straight lines or zig-zags. Sipes provide multiple benefits:
- a. Flexibility: Sipes introduce flexibility to the tire tread. When the tire encounters an uneven surface or deformations in the track, the sipes allow the tread blocks to conform to the irregularities. This flexibility enhances the tire's contact area with the track, maximizing grip and traction.
- b. Enhanced biting edges: Sipes create additional biting edges on the tire tread. As the tire rolls, these edges dig into the track surface, increasing the friction between the tire and the track. This improved grip is particularly useful on loose surfaces like dirt, allowing the tire to better dig into the material for traction.
- c. Water dispersion: Sipes also aid in dispersing water from the track surface. When racing on a wet oval dirt track, the sipes help prevent the formation of a water film between the tire and the track, reducing the risk of hydroplaning and maintaining better traction.
Together, circumferential grooves and sipes work synergistically to enhance traction on oval track dirt tires. The grooves help evacuate excess material and prevent hydroplaning, while the sipes provide flexibility, additional biting edges, and water dispersion, all contributing to improved grip and traction on the track.
The following pattern is commonly used on Modlite front tires, or anywhere that needs side bite. We recommend using a #2 Blade for the full tread block depth grooves. As always, only sipe at half of the available tread depth; in some cases, you want to reduce that depth to a quarter of the tread depth. You can always resipe the tire as the tread block wears. (Photo By Gary Cornelison)
