Seasoned or novice autocrossers and road racers may have some questions about the benefits of heat cycling and tire shaving. The first time a competition tire is used is the most important. During that run, its tread compound is stretched, some of the weaker bonds between the rubber molecules will be broken, which generates some of the heat. So before putting your competition tires into action, take a look at the key features and benefits to heat cycling and tire shaving:
Heat cycling applies to R-compound competition tires. To take full advantage of the tire's durability and traction, there's a required break-in process. By heating the tires up in a mild and easy environment, this allows them to cool down again and the rubber bonds to become stronger. As mentioned earlier, the weaker rubber bonds in the tread compound are broken. This is a good because the tires cool down and reattach in a more uniform manner, which results in more consistent strength and resistance for the tires to break again. This rebonding process occurs during the critical cool down period of 24 to 48 hours. Tire Rack offers a heat cycling service for $15 per tire. It's also possible to heat cycle competition tires yourself, however you must be careful not to overstress the tire (no hard cornering, acceleration or braking during this process). Next, you'd need to remove the tires from the vehicle so they can cool down and rebond without a load on them.
For more information on heat cycling, read "Competition Tire Heat Cycling Service."
Most competition tires call for a tread shave to maximize capability and longevity. I know it may sound counterintuitive stating removing tread depth results in longer wear, but it's true. With a racing slick, there's no tread design whatsoever, just a contact patch that acts as a single unit. With no tread blocks or water channels, there's no squirm of the individual pieces. While you need these design features for wet traction to channel the water out, they're not your friend in high-performance, dry only situations. By reducing the tread depth, you do a couple things to help with performance:
- Reduce tire's weight
- Reduce tread squirm
- Less heat generated
Tire shaving is recommended for competition tires for dry events that start at 6/32" of tread. However, it's also important to remember that once used, all tires will be much less effective during the next competition season. Therefore, we recommend that tires be shaved to a depth that's sufficient to last for no more than one competition season. If it's very important to you to do well in the one event you run a year, a tire shaved to about 4/32" will further enhance your performance. You can learn more about tire shaving by reading "Shaving Tires for Competition."