Ben Spies believes that his...
Ben Spies believes that his ability to conserve a tire during a race has been the reason behind many of his victories. Spies’ longtime crew chief, Tom Houseworth, told Sport Rider that the Texan’s tire management skills “kind of complete him.”
Last year contributing editor Henny Ray Abrams interviewed Ben Spies’ longtime mechanic, Tom Houseworth, as part of a story that focused on the crew chief/rider duo (“The Other Half,” May ’11). Houseworth spoke about all things Spies-related, but put special emphasis on the Texan’s ability to conserve a tire. “The next thing we worked on, which was really evident in World Superbike, was tire management,” remarked Houseworth, who went on to say that Spies’ ability to manage a lead from the front and conserve the tires “kind of completed him.” The ability to conserve a tire isn’t valuable solely on a world stage however, and riders of all levels can actually benefit from the skill.
When considering the cost of new tires, it’d be easy to assume that a fresh set of rubber will last multiple days at the track. Wrong. In fact, if your tire pressures are off, suspension settings imperfect or riding habits rough-edged, a new set of tires can get chewed up in just 15 to 20 laps at the track. Adapting your riding and better preparing your bike can therefore make your tire — and dollar — go that little bit further.
A number of factors contribute to tire wear, including track temperature, tire temperature, tire pressures and suspension settings. Among the most influential factors, however, are the rider’s throttle inputs through the corner. To better understand, it’s important to recognize how a tire is affected by the forces applied to it. A motorcycle tire — be it a DOT tire or slick — is designed to perform best at a given temperature, and heat is built into the tire when the carcass is under load. On the track and on the street that load comes from such things as throttle application, brake application and cornering G. Once the tire is past its optimum temperature, performance starts to deteriorate, as does the tire’s lifespan.
With improper suspension settings,...
With improper suspension settings, a tire will wear abnormally. But don’t throw out a set of tires that were torn up in practice so quickly, most tires with abnormal wear will clean up once the proper suspension settings are dialed in and tire pressures are set.
The art of conserving a tire requires the rider take each of the aforementioned factors into account. Your suspension settings should be considered first: Spring rates that are too soft are perhaps the most punishing and allow the bike to sag as you accelerate out of the corner, putting increased pressure on the tire’s carcass. Overly soft suspension also allows the bike to pump through the corner, which loads and unloads the rear tire. In both cases, the stress on the tire’s carcass will build detrimental heat.
Abnormal wear marks are the first indicator that a tire is being abused by incorrect suspension settings, and you should investigate further if your tires are coming off the track looking like they just went through a cheese grater. A few things to consider: If the rubber on the outermost edge of the tire appears shredded, that is an indicator that the tire is being overworked by a soft spring. If the treads of your DOT tire conversely appear to be cupped, that’s generally an indicator that your shock’s rebound settings are off. There are a number of other indicators to look for — so many that you’d likely get a headache trying to spot them. That said, if you’re unable to determine what direction to go with your suspension, confer with your local suspension tuner. Remember, the sooner the suspension is sorted, the later you’ll be replacing tires.
Along with proper suspension...
Along with proper suspension settings, out-of-the-ballpark tire pressures can severely ruin a tire — within just a handful of laps even. Too little air, for instance, and the tire’s contact patch will be too big, causing the tire to overheat. Too much air and the outer layer of the tire will be unable to reach optimum operating temperature.
Beyond dialing in your suspension for the track, it’s important to maintain your tires by checking and setting the tire pressures before each session. Tire warmers will work to your advantage here, since they not only reduce the likelihood of cold tire-induced crashes, but also allow you to set hot pressures without playing the guessing game. Be precise when setting pressures. Run too little air, for instance, and the tire will gain too much pressure as it builds heat on the track. Run too much air, in contrast, and the outer layer of rubber will not reach its optimum operating temperature. In either case, the tire’s performance on the track will be subpar, and worse, it will wear quicker. Also, be quick to put the tire warmers on when you get off the track so to avoid putting the tires through a heat cycle, which can also cut a tire’s lifespan significantly. Fortunately, most tires that have been damaged from incorrect settings will clean up once the suspension is dialed in and correct tire pressures are set.
Even though suspension settings and tire pressures play a role in getting your tire to go the distance, the biggest factor is your right hand. And while not as influential on smaller displacement machines, throttle inputs on middleweights and literbikes directly correlate with tire wear. Picking the throttle up through the middle of the corner and increasing corner speed is the best way to improve wear characteristics. The reason being that carrying more corner speed means you won’t have to whack the throttle on the exit in an attempt to make up time. In order to build up your confidence mid-corner, practice cracking the throttle open rather than leaving it closed all the way past the apex. You don’t need to grab handfuls of throttle in an attempt to test traction either, but rather slowly increase throttle opening smoothly to increase corner speed.
As you exit the corner, picking the bike up onto the larger part of the tire will also pay dividends. By standing the bike up as you accelerate harder, you’ll be using a larger contact patch and forcing the tire to work less. To practice, try weighting the outside foot rest and utilizing your countersteering techniques to stand the bike up as you accelerate off the corner.
While it’s important to carry...
While it’s important to carry more speed through the middle of the corner, it’s also important to pick the bike up on the larger part of the tire as you accelerate off a corner. By accelerating on a larger contact patch, you are essentially making the tire work less, which keeps overall tire temperatures and wear to a minimum. Casey Stoner demonstrates here.
The ability to conserve a tire requires you to take a number of factors into consideration. Not only must you get the proper suspension setup in practice, but you must also pay close attention to tire pressure recommendations as well as track and tire temperatures. There’s a direct relationship between tire pressure, wear and performance too. This means you can up the tire pressures and get better wear, but sacrifice grip slightly. Or you can run lower pressures and get better grip, but you won’t get much life out of the tire. The same applies to street riding to a certain extent. Come day’s end, the biggest difference is your ability to carry more speed through the middle of the corner. Avoid sudden stabs at the throttle as you exit the corner in an attempt to make up time and your tire will reward you with better wear.
While you may not be running 30-plus laps at a time like Ben Spies who uses his tire management skills to his advantage late in the race, the ability to conserve your tire and avoid abnormal wear will allow you to get a few extra track days out of your tires or maybe even an extra race or two. In the end, it’s money in your pocket. And a decent amount of money considering how much a set of tires costs these days.