"King" Kenny Roberts looked me straight in the eye and unflinchingly said, "I’ve always tried to do things properly," and such was his earnest demeanor, I believed him. The KR Tuned system engineered by his team and fitted to our Suzuki GSX-R1000 test bike shows a gain of 12 hp and 7 ft lbs of torque at the rear wheel; with a weight savings of six lbs. The full length, titanium twin-sided pipe has short carbon mufflers, and I found the throaty sound addictive—especially at higher revs on the track. It should not irritate the neighbors, provided you refrain from blipping the throttle too much at the crack of dawn. The system is very well made, giving credence to Roberts’ earlier—and very definitive—statement.
Power, of course, requires increased tire capabilities. I always feel bad for the rider when I see a bike on the street fitted with race-compound tires. Street speeds make it impossible to get enough heat into the tires and the subsequent lack of grip must be scary indeed. What is needed is a long-lasting street tire with enough grip to work at the track as well. Pirelli’s new Diablo Rosso has been targeted specifically for these two disparate demands. (Click image to enlarge)
The secret is Pirelli’s focus on its Enhanced (contact) Patch Technology and an exceptional new high-hysteresis compound based on its extensive World Superbike experience. The Diablo Rosso warms quickly and (Pirelli claims) lasts well—perfect for street use. Visually, it has a nicely rounded profile and a tread pattern that will obviously help clear water fast. Interestingly, those grooves stop short of the tire’s shoulder for maximum grip at the racetrack.
With a pair fitted to the GSX-R1000, I immediately found the Pirellis gave me a very secure, confidence-inspiring ride and great stability. At 32 psi front and 36 psi rear, there was minimal hunting over lines and ridges, even at freeway speeds. At the notoriously bumpy Streets of Willow Springs racetrack in California, the tires never felt unsettled or lacking in grip; my confidence in the front end was always 100%, even trail-braking into turns while leaned over. Out of slow corners, hard on the throttle, the big Suzuki can shudder the tire a little, but never truly breaks it loose; it is always predictable and controllable. The Pirelli Diablo Rosso seems to be that utopian solution for those hard-core sport riders who demand it all on the street, and sometimes on the track, too.