In a time when the world economy is slowing the rate of development for practically everything, it's rare to see many new or innovative products on the market. The two-year development cycle for Japanese sportbikes is a thing of the past-many bikes now have minor revisions, or even just "bold new graphics", instead of complete redesigns. Let's face it, times are tough.
Don't tell that to Metzeler. The tire manufacturer (along with parent company Pirelli) is seeing a high as of late with numerous new models being introduced. First was the sport-touring oriented Z6 Interact, next the Racetec K3 Interact. And now, riding the wave of success from the previous two, comes the Sportec M5 Interact. Designed to be the tire for the street rider who does occasional trackdays, the Sportec M5 is meant to be a tire that does it all on virtually any motorcycle.
With the continuous development of today's bikes, tire technology is forced to improve as well. What that normally means is a trade-off; high performance comes at the expense of tire life, comfort is sacrificed for stability, or wet grip exponentially degrades once the pavement dries off. Metzeler believes what it has created in the Sportec M5 Interact is a tire that sacrifices nothing and still achieves everything for the average rider who has one bike and wants to do it all.
So, how is that possible? The answer is three-pronged. First, Metzeler engineers started with the zero-degree steel belt it has incorporated in its tires since the beginning. Next, they developed a revised compound from the previous do-it-all tire, the Sportec M3, this one with 55-percent more silica content for quicker warm-up times. Lastly, like the rest of the Interact line, instead of multiple compounds seen on virtually all of its competitors, the M5 utilizes a single compound throughout but with differing tensions within the steel belts across the tire's profile to give it different personalities. Tightly wound belts in the center keep the compound rigid to promote longer tire life, loosely bound belts on the shoulder allow the tire to flex and create hysteresis-or heat formed while the tire is deformed on its side-which then allows the tire to grip during acceleration, and semi-rigid belts on the extreme edges provide stability at max lean when the only forces being applied are lateral from turning.
This is in contrast to the race-oriented Racetec K3 Interact, which has no silica content, instead relying on a revised formula of carbon black. The reason, it turns out, is because silica degrades quickly with high heat, and carbon black is better able to handle that stress for maximum grip in racetrack conditions. But according to Salvo Pennisi, Metzeler chemists were able to formulate a new kind of silica that's better able to handle those stresses, providing consistent grip faster-especially under braking-and for a longer period of the tire's usable life.
The most obvious feature of the new M5 Interact is its tread design. Resembling the Greek letter "Pi", Metzeler believes this pattern evacuates water more efficiently than the previous Sportec M3...and looks better, too. Grooves in the front and rear are always in touch with the ground, no matter the lean angle, to disperse water. That said, thermal imaging shows that compared to the Sportec M3 the new M5 has a three-percent larger contact patch when vertical, an eight-percent greater patch at 30 degrees of lean (for better acceleration), and five-percent more contact with the ground at 45 degrees. All told, Metzeler claims the new M5 can endure 125 miles of racetrack riding without compromising the tire's performance. Obviously, your mileage may vary.
Metzeler is pretty insistent that the new Sportec M5 Interact is a street tire first and foremost, but is also capable of handling racetrack duties. The company even invited journalists to Portugal and the Portimao circuit in the Algarve region for a combination street and track ride on a wide range of motorcycles ranging from a Suzuki Bandit 1250S to a BMW S 1000 RR (which was the benchmark motorcycle used to develop the tire). Because of the terrible weather conditions, many of the roads originally planned for the street ride fell victim to mudslides, practically ruling that portion of the test out of the question. Instead we focused our time on the racetrack, which actually resembles many features of a typical canyon road, like blind corners, elevation changes, as well as camber variations.
The dry session in the morning revealed that the higher silica content makes a difference-despite the cold ambient temperatures (hovering around 50 degrees)-one lap was all it took to ride at a fairly aggressive pace and reach knee-dragging lean angles. How do I know? Because the M5 comes with built-in lean angle indicators, the perfect item to gauge your performance...or that of your friends. Anyway, wear after this initial morning session was quite impressive as the tire didn't show any signs of abuse normally seen on a full race tire. The tire's profile promotes neutral handling, while edge grip is decent for a street-oriented tire.
In the later wet sessions, the M5 still showed neutral handling attributes while remaining stable. Clearly lean angles were sacrificed due to the rain, but where the tire is especially noteworthy is under braking. Even under emergency braking maneuvers it keeps its composure with minimal squirm or chatter.
All in all, for a tire that's heralded as the only one you'll need to do practically anything on practically any motorcycle, there's no question the Metzeler Sportec M5 Interact delivers. It's available in a 120/70 and 120/60 front and 160-190/55 rear sizes to fit most modern motorcycles. Pricing was not determined at press time. -TS