For many sportbike enthusiasts, there are few days in the saddle more satisfying than time spent at the track with good weather, honing your skills in a controlled environment. Sadly, not all of us can take up residence at our home circuits, and running slicks or DOT race tires isn’t the most versatile setup if our bikes also need to hit the canyons—enter the Pirelli Diablo Supercorsa TD.
Exclusively available in the North American market, and only obtainable through Pirelli race services, the TD stands for Track Day, as you might have guessed. Competing with the likes of the Dunlop Sportmax Q4, Pirelli is aiming this product at motorcycle riders who want rubber with grip in the realm of competition tires, without the fuss of tire-warmers and hassle of narrow operating temperatures. Though Pirelli positions the Supercorsa TD as an aggressive, high-performance track day tire, it is also DOT legal.The Supercorsa TD fills a niche between street and race-oriented rubber in Pirelli’s Diablo sport-tire hierarchy. The track-ready TD slots directly between the street-friendly and more than track-capable Supercorsa SP and the full-on DOT race tire, the Supercorsa SC. We should note that the SC is available in three hardness options, while the SP and TD are one-compound-fits-all.You might have noticed that the TD and SC are both labeled as DOT tires; however, we’d only condone street use with the TD. The reason a DOT race tire exists is to create a class in racing that didn’t rely on full-blown slick racing tires, even though the rubber compounds are not all that far off from that of a slick.At Ultimate Motorcycling, we always use tire-warmers with DOT race tires from any manufacturer and discourage our readers from using them on the street. Public roads are inconsistent, as there are shaded areas, water, debris, and your pace is continually varying due to traffic as well as other factors. For those reasons, you’ll never be riding fast enough, legally, to maintain the needed operating temperatures required for a DOT race tire.The TD is not subject to the same constraints, although we’d remind you that this is a fair-weather tire. The limited siping is excellent for maximizing the size of your contact patch, though that characteristic does not perform well in wet weather. In addition, the TD has more leeway in terms of suspension setup, whereas full-blown race tires are more sensitive to that sort of thing.Based on the Supercorsa SC tires used in the World Supersport Championship, Pirelli engineers revised the compound to ensure that the TD tires would rapidly heat up, while still providing more outright grip than their street-oriented SP tire. That is why tire warmers are not needed, and in that regard, Pirelli has done its job expertly.Additionally, the TD’s single rubber compound has no silica in it, which tire manufacturers commonly use a means to improve wet traction. The TD is about clear skies and fast paces. Those weren’t only changes, as the TD tires feature the latest profile developments from the Italian brand. The profile radius is aggressive, enabling quick, yet controlled handling. I immediately noticed it when comparing to the stock rubber of each of our test mules.Additionally, the carcass is optimized to deal with the rigors of the track riding, which include more aggressive braking and acceleration.I put the new Pirelli Diablo Supercorsa TD tire through its paces on three levels of 2019 motorcycles—the lightweight Yamaha YZF-R3, middleweight KTM 790 Duke, and Kawasaki Ninja ZX-10R superbike for a comprehensive assessment of this new track-oriented rubber.I packed up the truck and spent two separate days at Central California’s Buttonwillow Raceway Park on the 790 Duke and ZX-10R; both had balmy highs of 85 degrees, plus an additional day at the legendary WeatherTech Raceway Laguna Seca with the R3, where the high was a cool 63 degrees. Different bikes, different conditions, with similar results—precisely the kind of behavior we want out of a tire.I ran cold pressures of 30F/25R on all three bikes and saw consistent 3-4 psi growth across the board. That’s about what you will want to see in a tire and make air pressure adjustments based on feedback, as well as wear. If you plan on running these tires on the street, Pirelli recommends 36F/33R.Additionally, the North American Pirelli Race Support website provides a handy technical sheet with suggested warm psi settings. We advise that you use these recommendations as a reference guide and, if possible, speak with your track-side Pirelli vendor for information specific to your track.
We’ll begin with my experiences aboard the truly fun 2019 Yamaha YZF-R3. I have long said that there is nothing more entertaining than a lightweight bike with a great set of tires, and the TDs have only solidified that opinion.My day at Laguna Seca started with a fog-laden morning that verged on a light misting when rolling through one of the circuit’s signature features—the Corkscrew. What stood out to me immediately was the rapid and consistent heat-up times that I felt.Even in chilly weather and coming straight from the pits, the TD tires will begin coming into their own after barely completing three-quarters of a lap. That’s quite impressive, and to provide some context, I generally don’t start putting my faith into street rubber until after my first flying lap.By my second session with the TD laden R3, I’d throw caution to the wind and put my head down by the time I got to turn 9, also known as Rainey Curve. At that point, I would confidently be carrying enough lean angle to tap my knee to the deck—again, something I would shy away from on street tires in colder temperatures.Although I was running sizing that matches the 110/70 front and 140/70 rear that the R3 calls out for, the profile differences between its stock rubber and the Pirelli Supercorsa TD is readily visible. The much steeper profile wakes up the R3 to a significant degree, making an already nimble machine, even more so—an observation that stands for the 790 Duke and ZX-10R, as well.The turn-in rate is rapid, yet controlled enough to be entirely predictable, giving me loads of confidence so that I could put the R3 exactly where I wanted it. What stands out most is the compliance of a tire like this; if I needed to correct a line, the TD was happy to accommodate.Trail-braking into corners is a breeze, thanks to the amount of feel coming through the carcass. If the front is overloading or I am pulling too much lever over a rough patch of asphalt, like the one at the apex of turn 11, the TD signals that things were about to go south.Lightweight bikes are particularly kind to tires, as they do not have the power to spin the rear wheel excessively while driving out of corners. Their lower power also requires riders to optimize their lines, utilizing as much roll-speed through a turn as possible. With precious little juice at the wrist, you’ll need to rely on maintaining your speed to get the most out of a bike like the R3, and that requires trusting the tires underneath you.Laguna Seca’s Turn 2 is a long sweeper that will have a rider spending a great deal of time on the edge of the tire. Thanks to loads of grip on hand, I became increasingly greedy with the throttle off the apex, without ever truly breaking traction. I’m sure it’s possible with enough throttle and lean, but TD offers loads of grip to spare on a lightweight machine.With a non-adjustable fork and only spring-preload adjustability for the shock, the R3 offer little help in managing setup or tire wear. Luckily, that isn’t an issue on a motorcycle this size, and the TDs came out virtually unscathed.After a full day’s worth of riding, the front shows little to no wear, while the rear is barely showing its first signs on the left side. Tire wear is always dependent on skill level, but for someone of my pace, I could see getting as many as four track-days out of the rear before I’d think about mounting a new Pirelli Diablo Supercorsa TD.
I was excited to see where this test would go with a more powerful machine such as the KTM 790 Duke, which boasts a claimed 110 horsepower peak. That puts the peppy parallel-twin motor in the realm of your average 600 supersport, but with more torque on tap.With higher temperatures on the thermometer, heat up times were rapid. Within roughly a half lap or so at Buttonwillow Raceway, the tires felt as if they were ready to go. A concern I had with a tire designed to build heat swiftly is how it would perform throughout a 20-minute session. Although it heats up quickly, it seems to maintain and regulate its heat well, as evidenced by the complete lack of greasiness when the pace quickens in higher temperatures. Once the TD gets up to temp, the feeling stays consistent.Against my better judgment, I carried enough lean angle to tap my knee pucks down in certain corners in less than a full lap—again, not something I would normally do on street compounds.Saddled up on the 790 gave me access to a lot more horsepower, which meant I’d be diving into braking zones harder. The Supercorsa TD passed with flying colors in that department. Street tires do not have the same carcass stiffness as track-oriented rubber, so they will often flex too much, causing instability. Not only does that unsettle the chassis, but it causes me to lose faith in the front.Though I liked the front-end stability on the R3, the real test is what the tires do on middleweights on beyond, and my confidence was bolstered. The front of the TD is one of the highlights for me in terms of wear, feel, and grip. This tire gives me that extra bit of confidence when carrying faster entry speeds into long, sweeping sections of the course, mainly because I know the front won’t give way.When trailing into a corner on the brakes, the Pirelli’s carcass speaks to the rider and clearly translates what you need to know. Better yet, all that information is delivered progressively, and I am given clear signs where facing issues such as over-braking, lowered traction because of poor asphalt, or unsmooth steering inputs.With the more aggressive profile of the TD, the 790 Duke’s incredibly nimble nature is highlighted with a bolder color—getting onto the edge of the tire and staying there is done with ease. Mid-corner stability is superb. When it comes time to dice your way through something like the Cotton Corners chicane at Buttonwillow, you’ll be thanking that far steeper profile. Again, I was using spec sizing—120/70 front, 180/55 rear.Buttonwillow has several hard-driving corners throughout its layout. In those moments, being able to detect slippage, squirming, and grip from the rear is paramount. As the day wore on, I continued to lower the 790’s traction control from standard street settings to what KTM lists as being only safe with slicks.Eventually, I turned off the traction control completely for a few laps. The rear grip on tap with the Pirelli Diablo Supercorsa TD tires is a definite step above ordinary street tires and a slight step back from my experience of the mighty SC race tires. Still, I have a lot of faith in the edge grip available from the TD.Regardless of the settings I was in, the TD held firm, giving me an extra boost of assurance to get on the gas earlier and far more aggressively than I would with a street tire. One the few occasions that I initiated a meager slide, the 790 Duke was predictable and controllable.As the day progressed and the tire wore, I didn’t get excessive movement—the wear of the TD tires is incredibly linear. The front showed little profile loss and looked to be in excellent condition after a full track-day’s worth of riding in 85-degree temperatures. The rear did show some signs of wear on the right side. Running in a clockwise direction; Buttonwillow is right-biased. On the right side, the profile was beginning to lose its shape, showing the first signs of noticeable wear. Meanwhile, the left side looked terrific.The takeaway here is that the edge grip and profile maintained exceptionally well. Even after a full day, and with the right side a hair off the wear bar, I’d be comfortable running the rear for another couple sessions. Grip did drop off, though it doesn’t fall off dramatically; this coincides with the amount of profile loss observed. As a shelf started to develop, grip incrementally trailed off, yet wasn’t disappearing.
Liter bikes are notoriously hard on tires. Even smooth riders will eventually succumb to the siren song that is ridiculous power at the wrist. The 2019 Kawasaki Ninja ZX-10R’s superbike engine packs a serious wallop and is one of the most unrelenting inline-4s on the market, ready to slingshot you from the apex of any corner. It’s a tough job for any tire.One of the strongest points of the ZX-10R is its stable chassis. That stability comes at the price of making the rider exert more effort when flicking the motorcycle from side to side and on corner entry. The steeper, Pirelli SC-inspired profile is a massive help and immediately detectable here. Though the bike still asks much of the rider, it does decrease the effort needed to initiate a corner, for which I am thankful.Braking is another high-point as well. Pirelli tires tend to have a softer carcass feel. Due to that, they may not be as communicative as some of the harder-carcass having competitors. However, the feeling you get is quite good, and the edge grip is aplenty. In this application, the carcass almost has a damping quality that allows me to feel everything I want, while leaving the rough stuff out of the equation.Looking at the Pirelli sport tire spectrum, the ZX-10R highlights exactly where the TD falls—between the SP and SC. Its carcass feels harder than the SP and a shade off from the SC, which is an excellent middle ground.There is massive stability under hard-braking from triple-digit speeds, without any of the squirming that a literbike can instantly expose in a street tire. The front TD feels more relative to the behavior of an SC than an SP. The front communicated everything I wanted and allowed for deep trail braking, as well.Rolling through long sweepers, the TD front is rock-steady and is trustworthy on high-speed sustained turns such as Riverside. With loads of edge grip as my disposal, I felt confidently stayed on the edge of the tire, continually carrying more speed and twisting the grip harder when exiting the corner.The rear tells a similar story. On a big bike, I noticed more flex than I’d experienced on the R3 or 790 Duke, which makes sense as I’m dealing with more power and weight. Under hard acceleration, the TD rear stuck like glue, propelling me forward.If I were twisting the throttle too much or in an area of the track with low grip, the rear would give signals that it was stepping out. Literbikes tend to have more wheelspin due to their sheer force, and that can lead to sliding during hard-driving exits. When it did, and it was a rare occurrence for someone of my skill level, the slide or smearing was utterly predictable—letting go and coming back gently.With a handful of red flags marring the day, I only managed six sessions at Buttonwillow on the set of TDs with the ZX-10R—one of which was getting re-familiarized with the track. Though not a full day of riding, the front came away in excellent condition, while the rear was showing wear on the left, thanks to the left-bias of Buttonwillow’s counter-clockwise configuration.Based on previous experience with common street tires, the wear would have been much worse, and movement would have been quite apparent – that wasn’t the case here. Overall, the Pirelli Diablo Supercorsa TD tires did a great job.
Bringing It Home
The Pirelli Diablo Supercorsa TD is for a rider seeking the maximum amount of fun with the minimum amount of effort. Tire warmers, while not a particularly huge challenge, are still an extra burden on the rider. You need to set up stands, maybe bring a generator, take them on and off. It adds more steps and stress to a day that’s supposed to be all about fun and learning. That’s the surface benefit, honestly.The real benefit is the improved grip, feedback, wear, and performance that one gets with the TD over a street tire—even the Supercorsa SP V3, which is one of the most aggressive street compounds available on the market today. The TD gives the average rider a taste of what race tire performance is like, without narrow operating temperature windows. Maximum grip isn’t equal to the SC, but we’ll leave it to the top-level pro racers to exploit those tires to their fullest potential.Even better, the TDs can be used on the street, although we would like to point out that with massive amounts of grip and soft compounds, comes the compromise of low mileage. The tire is designed for performance, not longevity. If you want one of the most uncompromising, fair-weather, sport riding tires available on the market, the TD will be a good fit.Ultimately, tire choice comes down to application, so we need to ask ourselves what our needs will be. If you’d like to run a care-free track day, unencumbered by tire warmers – these are a great option for you. If we are focused on track riding and occasionally hit the canyons close to home, the TD could be a good option. If street riding is where you tend to spend most of your time with the occasional track day, the Pirelli Diablo Rosso Corsa II or Supercorsa V3 will most likely be a better choice.Available in a full range of sizes, the TD can be run on just about any sportbike currently on the market. I was extremely impressed with how consistent the behavior was across all three categories, despite each motorcycle stressing the tire differently. The Pirelli Diablo Supercorsa TD stood up to the ferocious power of the ZX-10R, made the 790 Duke even more enjoyable, and was transformative on the R3, making it a perfect racetrack training tool.While the TD more than admirably held its own on literbikes, I think they’re particularly suited for lightweight and middleweight bikes. High levels of grip combined with moderate power and reasonable tire consumption make a soft compound tire like the TD quite appealing.For those getting into track days, veterans of the circuit, or street riders who only care about hitting the canyons on hot days, the Pirelli Diablo Supercorsa TD is for you.West Coast customers should contact CT Racing for Pirelli race tires. Midwest, East Coast, and Canadian customers are encouraged to contact Orion Motorsports.Special thanks to Let’s Ride Track Days for its assistance with this story.
Hello everyone and welcome once again to the Ultimate Motorcycling podcast—Motos and Friends. My name is Arthur Coldwells.
Motos and Friends is brought to you by the Yamaha YZF-R7—Yamaha’s awesome supersport machine that is as capable on the racetrack as it is on the street. …and it’s comfortable too! Check it out at at your local Yamaha dealer, or of course at YamahaMotorsports.com.
In this week’s first segment, Senior Editor Nic de Sena rides the BMW K 1600 GT. This is the sporty bagger version of BMW’s K series of machines, those are the models with the awesome 6-cylinder engine. The GT has been given a little makeover for 2023, and Nic gives us his take.
In the second segment, I chat with one of my all time heroes—three-time World Champion racer ‘fast’ Freddie Spencer. I’ll do my best not to come off as too much of a fanboy here, but frankly it’ll be tough!
In my humble opinion, Spencer is a contender for the GOAT—greatest of all time. Sure, his career was a little shorter than some, and his number of championships falls behind the likes of Lawson, Doohan, Rossi, and of course Marquez. But at the time, Freddie literally changed the way motorcycles were ridden. 30 years before Marc Marquez, Freddie was able to push the front wheel into a slide, corner after corner, lap after lap in order to get the bike turned faster than anyone else. Freddie took completely different lines and was able to get on the throttle so early he could out accelerate anyone off a corner.
In the modern era, of course Freddie is the chairman of the FIM MotoGP Stewards panel. This is the panel of referees for all three classes of Grand prix racing. I talked to Freddie about his task there, and although for contractual reasons with Dorna and the FIM he cannot talk about specific riders, teams, or events, nevertheless his explanation of the job makes for interesting listening. It’s a tough job, and frankly I wouldn’t want to do it!
Actually—Ultimate Motorcycling is giving away five copies of the book—signed by Freddie himself—to the first five listeners who contact us with the correct answer to the question: How many national AMA championships did Freddie win, and which years were they?
Please email your answers to email@example.com and we will contact the winners and send you a signed copy of Feel. Those five winners will be announced on a future episode. Unfortunately for legal reasons this offer is ONLY open to US residents.
So, from all of us here at Ultimate Motorcycling, we hope you enjoy this episode!