Cycle News - Archive Issues - 2000's

Metzeler Sportec M-1 Tires philosophy behind it. In addition, the tire was designed to fit into a new market segment within the Metzler line, replacing two other tires in the process; the MEl3 and the MEl3R. One of the key goals was to develop a tire that wasn't only a high-performance street tire, but one that was capable of the occasional track day while still providing good mileage characteristics. On one end of the spectrum, the company has its excellent Rennsport line (which we, the Cycle News staff used in our openclass sportbike shootout back in April, issue #15), which is designed for racing (RS I, RS2) and ultra-high performance street applications (RS3), and on the other end is its touring line made up of the ME880, ME330/550, and the MEl4 sporttouring tire. The Sportec M-l has been designed to be the only highperformance street tire in the Metzeler lineup, fulfilling multiple roles by itself. (see diagram A). BY BLAKE CONNER PHOTOS BY TOM RILES here are so many options out there for the motorcycle consumer to consider when choosing motorcycle tires. It also seems that it is difficult for the consumer to- get unbiased information about the available products on the market. Many consumers resort to buying whichever tire their local dealer pushes on them - and that tends to be the most abundant tire on the dealer's shelves, or the expensive OEM specific tires. Metzeler has been making motorcycle tires for over 110 years, and currently is the only manufacturer that specializes solely on motorcycle tires. Metzeler has been at the cutting edge of motorcycle-tire design throughout the company's existence. It was the flTst company to develop tubeless motorcycle tires in Europe back in the 1970s, and it also pioneered low-profile tires in the same era. Most recently, it's zero-degree steelbelted radials have proven to be some of the best tires in the industry from the first MEZl tires in 1993, to the second-generation Sportec M-l that we recently sampled, Metzeler has continued to improve its offerings. Metzler's product-development team stressed the fact that the new Sportec M-l is an all-new tire, and not just an updated version of an existing tire. The tire is new in every aspect, from the materials, to the construction, and even the design T 28 OCTOBER 31. 2001 • cue that is generated by the tire. the harder the rubber compound has to be in order to keep the tire from wearing out too quickly. The zero-degree belting also keeps the tire from growing in diameter at high speeds. One of TIRE CONSTRUCTION There are a couple of key elements to the M-l that distinguish it from other tires on the market. The first is the use of zero-degree belts (see diagram B), which are designed to give the tire exceptional stability and minimal tendencies to tankslap. As you can see in the diagram, the steel belts run in the same plane as tire rotation. as opposed to a 45degree, or 90-degree angle, which generate more heat. The more heat I e n e _ lIS The new Sporlec M·1 • It's a tire all right. the huge benefits is that Metzeler can run softer rubber compounds without sacrificing durability, due to the fact that the tires aren't as prone to overheating. The most significant new technology in the new M- 1 tire is the way the steel belts are wound. The steel belts are first encased in what is called a bandina (see diagram C), in which two to three steel belts are encased in rubber for more accurate placing of the belts in the tire at assembly. The next technique is completely unique to the M-l, and that technique involves how the bandinas are spaced across the radius of the tire. The center of the tire has fewer bandinas, which are spaced farther apart to allow the tire to be more flexible and compliant under braking, creating a larger contact patch. The spacing of the bandinas get tighter as they work their way toward the edge of the tire, where the carcass needs to be the most rigid. A positive side affect is that this reduces the reciprocating mass of the tire, and the overall weight. Another key element involving how the tire performs is the way Metzeler has shaped the tire. The front tires have two different radii; the first is the radius in the middle of the tire that allows the bike to

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