Sports Touring tires have an incredible tough job. They have to suit all types of motorcycles, from 200 horsepower superbikes to lightweight commuters and heavyweight tourers, give confidence in temperatures as low as 5º Celsius, cut through the heaviest rain, give excellent grip on dry roads, and provide a sporty steering characteristic while remaining stable. On top of all that, they’ve got to give thousands of kilometers of life, too.
Logic suggest that creating a product to achieve all this would be impossible, as the soft compounds needed to generate feel and confidence in cold, wet conditions are the very same compounds that can be easily overheated in warm, dry, high-kilometers situations.
But in recent years all the leading manufacturers have now created products to give riders around the world the ideal solution for all types of road riding, which is why sports touring tires represent the majority of all motorcycle tires sold around the world.
Lets look at the Metzeler Roadtec 01 and the technology that is used to achieve the impossible.
For the Roadtec 01 tires, Metzeler uses a patented design that utilities a radial carcass and a single layer belt of steel cord. If you think of the rolling direction of the tire, the belt is wound circumferentially giving an angle of almost 0º. This allows Metzeler to tune the winding spacing to allow varying stiffness levels from shoulder to crown.
The profile of the Metzeler Roadtec tire is unique. The curvature has been designed to increase the width of the contact patch. As well as doing wonders for rear grip, a wider contact patch actually gives more kilometers as it shares the driving forces over a larger surface area.
Metzeler refer to this as chemical grip. The Roadtec has a dual-compound rear made from 100% silica at the shoulders; silica is the secret to amazing grip in the wet or on poor surfaces, but it lacks longevity which is why the middle strip of the tire has a different compound. The front is made of a single, 100% silica compound.
The tread pattern works in conjunction with the carcass and compound of the tire to give wet grip. A sport-touring tire’s tread should displace water at all speed ranges, and is focused to fling it from the middle to the outside edge of the tire. Metzeler has maximize the pattern’s ability to do this by increasing the stiffness of the tread blocks.
Metzeler has a full-time test team, including riders, technicians and fitters. Tires are tested on a range of motorcycles, different weights, operating loads and in various ambient temperatures and conditions. Testing takes place both on closed circuits and roads. Metzeler probably cover half-a-million kilometers from start to finish.