MO Tested: Pirelli Diablo Rosso Corsa II Tire Review
Multitasking in Monterey on Pirelli's first multi-compound motorcycle tire
It was rough duty but somebody had to do it: Hang out at Laguna Seca’s World Superbike/MotoAmerica race all weekend so as to be there early Monday to ride around on Pirelli’s new supersporty street tire, the Diablo Rosso Corsa II. It is altogether fitting and proper that we should do this, since Pirelli has been the official tire of the WSBK since 2004 and will continue to be through at least 2020.
To celebrate that, Pirelli started doing this day-after Laguna track day more than a few years ago, inviting out not just a few lucky journalists, but also a bunch of its dealers and distributors along with sundry cool people and hangers-on. Lots of them bring their own motorcycles; lots of them (me) are coddled by the 42 new bikes Pirelli talked the manufacturers into bringing out for people to sample. Our accomplices at Trackdaz were also there to keep things as safe and orderly as possible. So we all got there at 8 am, but couldn’t ride till about noon because of fog.
Good conditions to test the new tire, really, as the fog began to lift but the cool and damp remained. Since the original Diablo Rosso Corsa appeared in 2010, says Pirelli, “torque and horsepower outputs have increased significantly and the introduction of sophisticated traction control systems and cornering ABS have enabled these performance gains to be applied by more riders able to reach greater lean angles.” Reaching greater lean angles requires carrying more speed.
To keep up, the new Corsa II incorporates everything Pirelli’s learned in the last eight years to come up with a tire to handle the new reality. This one “is intended for riders of mid-high performance motorcycles who enjoy a sports riding style on the street and not just on the racetrack. They desire a tire with fast warm-up, sports agility, excellent grip and consistent performance ready to compete against the challenges of everyday use. Pirelli have now transformed racetrack performance into street versatility to guarantee top performance also on road.”
To achieve that, the Corsa II is Pirelli’s first foray into multiple compounds. For the rear tire, a new combination of compounds has been developed; the rear is divided into five zones with three different compounds:
The central compound (green) has high silica content, which promotes excellent stability at high speeds, uniform wear and good mileage. The intermediate compound (red) that covers the intermediate lean angles has a formulation of 100% silica, which provides excellent chemical grip on dry and wet surfaces, and is supported by a harder compound in the substrate that enhances stability and precision when cornering. The compound on the shoulders (yellow) is a 100% Carbon Black compound “with a high degree of hysteresis that transforms blend compression into heat, thus providing a fast warm-up. It also has a broad working temperature range, which guarantees grip and stable performance regardless of the load. This compound employs the same racing resins used in the Diablo Supercorsa designed for use in high temperature and high stress situations typical of racetrack riding.”
The front Corsa II does away with the rear’s center compound, using the 100% silica compound instead for great grip even in the wet – and again with the full carbon black edges for serious grip at high lean angles.
The profile of the new tire is different, too; the more triangulated shape enhances quick transitions – “maximum leanings” in Pirellispeak – and maximum stick at full lean where the shoulders are broader for a bigger contact patch.
Newfound levels of grip, traction, and therefore speed led Pirelli to adopt a new, race-derived casing for the rear that it calls Lyocell, “a casing with a significantly lower deformation ratio than that of the fibers normally used in street tires. The high-modulus Lyocell fiber casing is an exclusive, patented Pirelli technology developed through the company’s participation in the FIM Superbike World Championship.”
The new carcass is able to deal with the higher stresses imposed by modern bikes, while also supposedly absorbing bumps just as well as the previous Rosso Corsa. Laguna Seca is pretty smooth these days, so that’s a hard thing to confirm. Overall, though, the Corsa II seems to do everything you could ask of a sports tire: It comes up to temperature quickly on a cool day and after a lap had as much edge grip as I was willing to ask for on an R1S. To be perfectly honest, I was so smitten with the Panigale V4 and V4Ss that Ducati brought out, I spent most of the day on those bikes and on an Aprilia RSV4 RF, before realizing they were rolling on Pirelli’s racier Supercorsa rubber.
On the Supercorsa, I could do no wrong. I still couldn’t do much right compared to all the fast people like Valentin Debis, Jake Zemke, et al, who would occasionally pass me as if I might as well have been riding a Barcalounger… but if they hadn’t been out there I’d have sworn I was on lap record pace and the Supercorsas never gave a moment’s pause.
Luckily, MO’s guest tester and WERA Expert Fabrice Vilder (who also goes past yours truly like a man at a bus stop) was also on hand. Fabrice rode on both tires, and was equally as impressed as he was the first time he rode the Rosso Corsa II last month:
I had the opportunity to test the new-for-’18 Pirelli Rosso Corsa II during an Aprilia day at Buttonwillow a couple months ago. I was amazed to see what Pirelli had achieved in building a triple-compound tire that offered such levels of grip, consistency, stability and longevity.
This tire has about 50 hard laps on various Tuonos/RSV4s, and kept giving me great confidence at full lean – the last strip of soft and sticky compound was clearly felt. Power slides were as consistent as can be, stability in general was exemplary. I would typically go out at about 70-75% for the first lap, then hammer it. The tires withstood heat cycles effortlessly. Of course the Corsa II doesn’t offer the outright performance of the more expensive Supercorsa, but if you are a street rider who doubles as track day aficionado, chances are you will run out of talent before you run out of grip…
And there it is in about a 1200-word nutshell. If you’re racing for big money, you need to make the big investment in the Supercorsa SC or comparable. But like Fabrice says, for all the rest of us schlubs who ride sportbikes and only get to the track once or twice a year, the new Corsa II draws on Pirelli’s vast experience to produce a sport tire that seems cutting-edge and hard to beat.
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