Pirelli Diablo Supercorsa SP - V4 Review

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Pirelli’s new Diablo Supercorsa SP - V4 provided amazing performance over two days of testing, both on the track at a 110-degree day at Chuckwalla Valley Raceway and then on the street two days later. (Jeff Allen/)

The promise of high-performance sportbike tires is that they can provide excellent performance for all conditions when riding on public roads, and then be able to slay asphalt within the confines of a racetrack at a trackday. There are a lot of tires on the market that make that claim, some do it better than others, but our recent experience with Pirelli’s Diablo Supercorsa SP - V4 proves that the Italian company delivers on that promise.

Like so much of motorcycling, tire technology is advancing at a ridiculous pace. And to be honest, it had to. The ever-rising performance of sportbikes in particular has meant that tire companies have had to keep pace, or even stay ahead of the horsepower race.

According to Pirelli’s motorcycle product manager Silvio Frare, “The gap between the hypersport bikes that you can buy and racebikes has become much closer over the years. In some cases there is only a 40-to-50 horsepower difference between the two. It’s way closer than what it was in the past, and yet the motorcycle manufacturers keep making more and more powerful motorcycles. We are very close to the 1 horsepower per kilogram level.”

Chuckwalla Valley Raceway in June is about as challenging a test for tires as there is. (Jeff Allen/)

In Part 2 of our recent 2023 Hyper-naked Comparison, two of the bikes tested produced amazing levels of power, including the winning 173-hp Ducati Streetfighter V4 SP2 and the 185-hp BMW M 1000 R. That’s rear-wheel power measured on the Cycle World dyno, not manufacturer’s claimed crankshaft power.

Due to time constraints, our testing on the racetrack would take place prior to the bulk of our street testing, and have to be conducted on the same set of tires for each bike. The potential problem was that the track portion was in late June at Chuckwalla Valley Raceway outside of Palm Springs, California, with ambient air temperatures hovering around 110 degrees in the middle of the day. Could the tires possibly survive such a torture test and still be roadworthy?

At the end of our day at Chuckwalla Valley Raceway, the Supercorsa SP - V4s on the 173-hp Ducati Streetfighter V4 SP2 looked amazingly good. (Blake Conner/)

Our testing at Chuckwalla included three riders lapping all day for impressions and photos, and then going for some quick laps at the end of the day. On the track we ran Pirelli’s recommended hot tire pressures of 33 psi front and 30 psi rear, and checked them throughout the day to make sure they were accurate. According to Frare, one of the design goals, in part because it’s a street tire, is that “with the SC3 compound on the shoulders you do not need tire warmers at the track.”

From our perspective, performance was very impressive, offering that promised quick warmup, very neutral and predictable handling characteristics, and consistent grip throughout the day. Due to timing at the track we had to wait until the very end of the day before letting Bradley Adams loose to rip off some quick timed laps. The Supercorsa SP - V4s weren’t bothered by this in the least, providing excellent performance even after a ton of laps earlier in the day.

When we wrapped up our riding, we estimated that each motorcycle did a minimum of 45 laps between the three of us. So we were shocked at how good all three sets of V4s looked when we concluded the track test. An interesting side note is that Chuckwalla is pretty abrasive on knee sliders, with Adams smoking through them in short order, so our curiosity was raised as to how the tires survived with minimal signs of graining on the surface, looking as if they not only had more than enough life left for the street, but could have easily tackled another day at the track. Remember, we’re talking about bikes making in excess of 170 hp at the rear wheel.

Due to timing restraints, we needed to conduct our street testing after our trackday; the Pirellis did not disappoint and provided excellent performance with the tire pressures adjusted to the recommended pressures suggested by the respective OEs. (Kevin Wing/)

For our street ride two days later we used the tire pressures recommended by the motorcycle manufacturers for their respective machines. For example, BMW recommends cold pressures of 36.3 psi front and 42.1 psi rear for the M 1000 R. In the canyons of Malibu, California, the tires again performed flawlessly, offering excellent grip throughout our day of testing. Steering remained neutral and predictable with no real change compared to the stock tires that all three machines were delivered with. After all of the heat cycling and laps from the track day, the V4s didn’t show any signs of reduced performance.

This illustration shows how the SP - V4 differs from other Supercorsas in Pirelli’s range. (Pirelli/)

A look at the tire’s structure reveals it’s based on a profile derived from Pirelli’s World Superbike tires and uses the same materials as the Diablo Superbike slicks, but the construction is optimized for the improved stability necessary on road. “For the V4 we’ve had to blend our SC and road technology,” Frare said. “For example, to be able to use road pressures on the road and use racetrack pressures on the track. For this reason specifically, the SP and SC bead structures are quite different, because the SP has been designed with both of the specificities in mind. It’s a reinforced sidewall that can perform equally well at road pressures and racetrack pressures.

“The SP versions must be compliant with EU, DOT, and other regulations,” Frare added. “But the starting point is from the SC racing range, then we use all of our expertise from our road applications and make the best-performing street tire we can make.”

Pirelli’s Supercorsa SP - V4 uses dual compounds front and rear, but the rear has a dedicated base layer. (Pirelli/)

Both the front and rear tires are dual-compound but have different construction. The front has what Pirelli calls a Dual-Compound Cap and Base Layout, with the center tread designed for high-speed stability and braking stress, while the base layer offers thermal stability. On the shoulders is the Racing SC3 compound. The rear has a dual-compound construction that has a dedicated base layer for better thermal stability. The Racing SC3 compound is employed on the shoulders with a harder and more durable compound used down the center.

It is this structure that helps give the SP - V4 its durability. It provides the tire with the ability to manage heat, which is ultimately the enemy of tire life. “The ability of the compounds to withstand abrasion has improved a lot in recent years,” Frare said. “A big factor is our ability to optimize the shape of the tire’s profile. With modern bikes’ lean angles reaching 55, 58, 60 degrees, if you can finely tune the amount of rubber that is on the road when you are at maximum throttle, the more trust the rider will have in grip, but also the tire will provide more durability.”

“Racing is a tool of development and we use the information gained to build the tires for the road that will provide the customer with the most satisfaction,” added Salvo Pennisi, head of moto and cycling testing. “With such powerful production motorcycles, the development of compounds and construction for racing and the road have been developed in parallel.”

If you believe the marketing-speak, the SP - V4 is better in every regard compared to its predecessor. (Pirelli/)

Every tire manufacturer out there delivers a load of marketing-speak to convince us that its product is the best. But it’s really refreshing when the actual performance of the product handily exceeds the expectation. In the case of Pirelli’s Diablo Supercorsa SP - V4, we ended up not only very impressed by their durability, but the grip proved to be excellent and consistent both on track and on the road. We also felt that the tires complemented the handling characteristics of the bikes we were testing and enabled us to get the best possible performance out of each machine.

The fact that the tires also saved us the hassle of having to switch all the machines back to their original OE tires for street testing was simply the icing on the cake. The Diablo Supercorsa SP - V4 is ultimately everything that Pirelli promises and more, a tire fully capable of serving double duty as a high-performance street and trackday tire.

Available Sizes

Pirelli Diablo Supercorsa SP - V4

• 110/70-17 (front)
• 120/70-17 (front)
• 140/17-17 (rear)
• 150/60-17 (rear)
• 180/55-17 (rear)
• 180/60-17 (rear)
• 190/50-17 (rear)
• 190/55-17 (rear)
• 200/55-17 (rear)
• 200/60-17 (rear)

 

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