Pirelli tire selection

If it works, it works...I've never seen or experienced any additional benefit to running a SC2 rear except on colder weekends. Ran an entire endurance stint on a SC0 at PittRace this past season and it was great, but usually SC1 rear is my "do it all" compound

 

I've switched to SC1/SC1 now. But will certainly give the front SC2 front a try this next season.

 

Is the move from 180/55 -> 180/60 -> 190/60 an effort to mimic 16.5' wheel/tire feeling on a 17" rim?
(I've never run 16.5" , but I'm sure the WSS paddock has)

 

WSS was never on 16.5" slicks.

 

I meant to say, the racers in the paddock probably have some experience running the 16.5, while they were coming up through the ranks / different championships etc., so to speak. Not necessarily the world super sport series, per se. But, your point is taken - the tire is developed from the series for a 17" rim. So, there goes another of my theories. Lol.

 

WSBK changed over to 17" in 2012 or 2013 I think.

The jump from the 180/55 to the 180/60 is very substantial. The jump from 180/60 to 190/60 is less substantial, but has been an improvement in just about every way.

 

As tire technology has improved over the last 15 years manufacturers didn't see a reason to continue with 16.5 RR tires as it didn't help build better radial products. So WSBK and MotoGP made the push to switch to 17s, and for F1 they're finally making the change from 13s to 18s too next year.

I see where you are trying to go but it's not to mimic the supertall sidewall of the 16.5 but more to improve the tire's shape to increase the contact patch and increase side bite to keep up with the advances in the chassis, suspension, and electronics currently used.

 

The tire manufacturers build tires to extract max performances from the chassis/suspension/ electronics , and in turn the manufacturers change machine characteristics to exploit the available grip / performance from the tire.

All that is fine, but the glitch in the script is - Don't the bikes on WSS (Pirelli) and Moto2 (Dunlop) have regulations that allow changing the swingarm etc. ? Therefore, where does that leave the average rider with legacy frame / swingarm / electronics ? Granted there are improvements that are useful across the board - quick warming/ durability etc. while we've seen seismic changes on the liter bike category, the 600s haven't really changed much. It would've been useful if the tires were tested on national series, as opposed to the aforementioned WSS/Moto2, but then the best riders competing in the world series are also the best people to test with - and no better testing ground that competition.

Anyway, all this is just academic. I'm sure the variables are taken into account / the multi million business that it is. Reality is that the 180/60 tire was a big benefit from the 180/55 even to a mediocre rider like me. I would've had no qualms about the 190/60, other than the worry about swingarm clearance on old 600s. we'll just try it and see where it goes. Regardless, I thank you and Mike (MDM) for chiming in and providing clarity.

 

The difference is you can buy the tires they're using in WSS at your local race track and we can use that trickle down tech in addition to what we learn being at the race track to help you, the end user.

Are you having clearance issues radially or axially? What motorcycle? If it's radially, drop a tooth on the rear sprocket; you'll end up with the same final drive ratio to the track you had before due to the larger circumference of the 190.

If axial clearance is the issue, the solution is simple; drop $8k on a bespoke Suter swingarm.

 

A newer model used bike would probably cheaper than that swing arm.

 

But Pirelli tires are tested in national series(s) all around Europe and the world. And that feedback along with feedback from the US is given to the R&D and race engineers in Milan. But you as a racer have options if you want to race Pirelli. There's a SC1 & 2 180/55 slick, a 180/60 SC2 & 3 but if you want to run at the pointy end fitting the latest and greatest probably should be done

 

I don't know yet. Due to try the 190/60 in 2022. Track Bike is a 2007 CBR600RR with 15/43 gearing. Endurance Bike is a 2014 GSXR 600 with 45 rear sprocket. We'll go with your recommendation of dropping a rear tooth if there is an issue with radial clearance. I think I'll embrace 2blueyam's recommendation of buying a new bike than invest in a suter swingarm, if there is an axial clearance issue.

My ignorance is showing. Apologies.

 

Really glad I came across this thread. I am looking for some guidance here, @Pneumatico Delle Vittorie perhaps you can help me out. For some context, I am racing in Southern Ontario, Canada. We see ambient temperatures in the range of 15c at start of season to 30c in mid summer. The asphalt on our track surface is not very abrasive.

1. I want to clarify something I read in this Pirelli article; that as track temperature goes up, the grip decreases. I am sure this can not possibly be true. What I expect is there to be a range where track grip is optimal. If we go over OR under this range, then we have poor traction. The question becomes, what is the range? For future reference, let's assume X-Y Celsius is the range where tarmac is with optimal grip.

2. When we are below X (Ie. poor track grip due to cold temps), what compound should we use? My inclination is SC1F and SC1R.

3. When we are in the range of optimal track grip, what compound should we use? My inclination is SC1F (for max grip at possibly slightly reduced stability) and SC2R. Here is where I struggle a bit. Why do we want a SC2R when grip is optimal. Here is my guess; let's assume we made the "wrong" choice and used a SC1R. Because we are using a soft compound and grip is optimal, the tire penetrates the surface very well which generates lots of friction/heat. As a result, we superheat the contact patch which in turn causes cold tearing on the SC1R. So, we must use a SC2R to combat this. However, wouldn't the SC1R provide better traction anyways (at the cost of cold tearing)? Is my theory here even correct?

4. When we are above Y (Ie. poor track grip due to overheated surface), what compound should we use? My inclination is SC2F (for max stability at possibly slightly reduced grip) and SC1R. We need the SC1R since track grip is poor and we need the softer rear to compensate and get grip.

5. What is X and Y? I realize this is tough to answer as will vary track to track but an idea would be nice to have.

 

Wow those are a bunch of questions and what you are looking for is a bit weird so it's going to take some time to sort thru them. AFWIW the only tracks in Ontario that I haven't been to are Grand Bend and Calabogie.

And have you ever heard of a guy named Kevin from Orion Motorsports and did you read the very first post of this thread?

 

Operating temperature of the tire matters a lot more than ambient temperature or the temperature of the track. Pace is important. Setup is important. We've set lap records with ambient temps in the low 50s (F) with SC0 rears.

To get YOUR range, get a helper and an IR gun to stand on hot pit. PSI and temperature and the relationship between the two matter a lot more than the scale you're looking for. And once you're beyond a certain pace, forget that SC2 rears exist. Since there are no reference points for what track, motorcycle, or pace you're inquiring about, a real answer is almost impossible to give.

 

I primarily race at Grand Bend in the regional series but will also be racing at CTMP and Calabogie national rounds as well this year. Not sure if I know Kevin off the top of my head.

I did read throughout the thread which had good usage information, but I was hoping to understand a little more in depth as to why a SC1 on a cold day would tear and be a bad choice.

Yes, I understand this. I find it interesting that you discount the SC2 fully; and also interesting that you were able to get such strong lap times with a SC0 on a cold day. It was my understanding that a SC2R would perform better than a SC1R in the cold but perhaps I am wrong here.

 

Kevin owns Orion Motorsports and is the Eastern US and Candian distributor for Pirelli RR tires and is based in Ontario.

 

Ah, in that case, we did meet (albeit briefly). He came out to Grand Bend at one of the rounds last year.

 

Operating temperature.

And I didn't discount the SC2 rear fully at all. I said, beyond a certain pace, they are no longer viable race tires especially since the SC1 has such a wide operating range.

 

im not going to dispute a single thing you ever say but I'd like to know your opinion on a track like Eagles Canyon in texas where no matter what and who's riding an SC1 looks like a cheese grater hit that tire after about 10 laps. Even our Pirelli tire guy said we'll be racing on SC3 rears when CMRA goes there for the first time in august. SC3's wear perfect, SC2's pretty good but not available in current 190 600cc sizes and sc1 fronts wear perfect while my last sc1 rear was destroyed in record time