Cycle News - Archive Issues - 2000's

Dunlop 5 Daytona Tire Test: Part /I material such as Kevlar, and the tread compound. Pirelli uses a Analysis) work. Previous to that, motorcycles had to share an existing facility with the car race shop. "It either confirms or predicts what we're intending to do. We can monosteel band similar to Michelin, but they've also been using an aramid called PEN, polyethelene napthalate that is stronger and lighter than the traditional aramids. "If you reduce weight, you reduce heat," Allen said, but to a point. "The finer the material, the work out the stresses prior to making the tire." The trick, at Daytona, is getting the balance between the two compounds on both the front and rear more flexible. You can change the stiffness a number of ways." Even as you look at a tire, the rubber on the sidewall isn't the same as the rubber of the tread. If tires. "No two corners of the motorcycle have the same compound," Allen said. The front is medium on the right and hard on the left, the rear is soft on the right and very hard on the left. The compounds themselves are you change tread rubbers, sidewall rubbers remain the same, fairly hard, fairly stiff. That rubber isn't formulated for grip. It has to be consistent, with a consistent spring rate, no matter what the compound. The softer the carcass, the bigger the contact patch. It works up to a different because they suffer different forces. The front scrubs off speed, so the rolling resistance is different. The rear tire spins off most every corner. The compounds are split evenly down the center, which was the way the original dual-compound tires were made in the early '80s. "We cut them apart and glued them together in '81 - '82," Watkins said. "There was an instability prob- point, then there are regressive effects. "You're working with a fine envelope with the spring rate of the tires. You step outside of that and the tires don't work," Allen said. Tire stiffness and construction is lem when we put them together. The problem isn't gluing them together, the problem is getting them to work like a normal tire." as important as compound, because as suspension advancements are made, and the tires spend more time on the ground, the Dual-compound tires are made by extruding two different types of tires are increasingly being asked to do the work of the suspension. "Riders race with different rubber and joining them together on the carcass. Modern tread-extruding setups, some race with hard springs, some with soft springs. It's asking a lot of one tire to cover all circumstances," Allen says. And the circumstances change during the race. There are two stages to tire performance. The first relies on the machines can join up to seven compounds of rubber in a single tread, but Dunlop can get much more precise placement of the compounds by using a manual system it developed and patented specifically for Daytona. compound to give the properties to the tires. When the compound deteriorates, the structure compensates to give lateral grip. You could make a tire go faster with a certain con- Heat is an enemy of tires and it is generated by a number of factors, including motorcycle speed and weight and the weight of the tire itself. The tire is made up of three struction, but the compound o"';ly goes so far if it's not supported by the tire structure. When tires overheat the compo- principal parts, a rayon or nylon carcass, an aramid band made of Dunlop's main men: Dave Watkins and Jim Allen nents won't stick together. A typical Team Hale Maybe, Maybe Not If everything falls into place, Mike Hale could be racing a Ducati in the 2001 AMA/Chevy Trucks U.S. Superbike series, but he'll only do it as a first-class operation. The Texan, whose last motorcycle race was on the Team Proton KR Modenas at the Argentinian GP in 1999, came to Daytona to show potential backers that he could still be competitive. Judging from his first day's efforts, they have to be impressed. Riding on a day of limited track time, Hale turned in a best lap of 1:52.11 on a leased CompetitionAccessories.com Ducati, the same bike which Larry Pegram last rode at the final AMA round at Willow Springs. As a point of comparison, John Kocinski was the fast rider of the day with a time of 1:50.69 in his maiden voyage on another CompetitionAccessories.com Ducati. Riding a well-worn vintage- 1998 Ducati the second day, Hale improved his time to 1:51.9 in 20 laps. "I'm getting back on a bike and showing people I still know how to ride," Hale said on a damp Tuesday moming, the day after his outing. "My manager, Cary Agajanian, and myself are working on the possibility of putting together our own team for next year. Ducati puts together a good program for satellite teams. It's good competitive equipment to go racing with." The backing for the team would come from a number of corporations that Hale and his management team have been in contact with. "I'm only going to do this thing first class all the way. If we're three-quarters of the way there, I won't do it." Parallel to this effort, Hale is continuing to pursue a car-racing career with one possibility being a limited car campaign and a full AMA campaign. Hale said he could race as many as 15 rounds of the NASCAR Craftsman Truck Series and selected ARCA races, building that schedule around the AMA calendar. With the same sponsorship for both efforts, Hale said he wanted to "raise the level and awareness of motorcycle racing." There isn't a formal deadline for the decision on whether to go forward, but Hale said it needed to done quite soon. "I don't want to show up at Daytona not prepared." Since he hadn't raced for over a year, and hadn't ridden a Superbike since riding the Fast by Ferracci Ducati in 1998, Hale said he was "riding a little bit tight, not hitting my usual brakemarkers yet. I'm not 100% up to speed. I grew up racing bikes, so it's second nature to me." Hale flew out after the second day to return to Texas to work on putting the program together. Even if he doesn't go racing, the Texan has already begun a second career on television. He's the host of a show called "Motovision," which he describes a "technical motorcycle show for the average street rider. It's a new concept for the motorcycle world. We get our hands dirty. Show people how to do stuff." Bobby Weindorf, Hale's long-time mechanic, is the Motovision mechanic, though they'll use anyone who can provide expertise for the chosen subject. Paul Thiede of Race Tech and Erion Racing's Rick Hobbs both worked on the pilot. The pilot, which dealt with suspension, has been filmed and is currently being shopped around. Speedvision, the ESPN networks, and TNN are the most likely venues for the show. Hale said they'd also have an Internet presence. "We're looking to take the thing international," Hale said. "We have good contacts outside the country, in Canada and England. Anywhere they can understand me." rear racing tire has one body ply or it might not have been mixed and two or three breakers, belts or bands. The rubber that coats belts or bands gets extremely hot long enough. because of the heat generated clicked into fifth gear on the east between rubber and the belts. One banking during the 1998 tire test, result can be laminations, which are not considered to be severe. Laminations are little thumbnail or fingernail-sized pieces of rubber. A little pockmark will appear where there is a piece missing out of the- Ben Bostrom learned about tire failure the hard way. Just after he'd his rear tire disintegrated and no one's quite sure why. "Basically what we were left with was destroyed to such a point that it was difficult to pin down what tread. Generally the bottom of the lamination is quite shiny, revealing a tread compound that hasn't been mixed properly for some reason, or JANUARY 17. 2001 • cue I e n e _ s ure, a significant failure which happens when the tread separates from was mixed with a bad component, 18 happened," Allen said. the belts, though generally with a It may have been a casing fail-

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