Pirelli Tire Pressure Thread

SinisterBabo

Bumblebee
Let's get some tire pressures going on. Interested to see what people have heard/put to use/official pressures (click for Pirelli site):

Looks like Pirelli is pretty consistent across most tires based on wheel mounted:
Front
29/30-32 PSI Front Cold
23-26 PSI Rear Cold

30-35 PSI for Supercorsa V2s or 32-36 PSI for Superbike <-- Does this indicate that the slick is a softer carcass?
25-28 PSI Rear Off-Warmers

I usually use 31-32 front 26 rear on SC2/1 after being on warmers between tech and the end of the rider's meeting.
 

vinny337

Vin is in...Beastmode!
Control Rider
Trying Pirelli for the first in years so I've been experimenting with the pressures and compounds. Hot off the warmers I run the SBK SC1 36F/24R and SC2 35F, I haven't tried a SC2 yet...still figuring things out.
 

MDM

New Member
Hi, I guess this can serve as my semi-official introduction to the N2 online community. My name is Mike Faillace and I own and operate MDM. We're based just outside of Philadelphia and we've been around for over 10 years serving the track day and racing community and I've been a Pirelli man for as long as I've been involved in motorcycles. First, as a track day rider and then as a racer and now, for the past several years, as the official race tire vendor for this region. I've won a lot of races and championships on Pirelli tires and have worked with a lot of racers and track day riders over the years and have been fortunate enough to have my name associated with 1000s of race wins and hundreds of championships. I have crew chiefed for many CCS racers, run pit crews for a number of Daytona 200s and have most recently served as crew chief for Xavier Zayat and Brandon Paasch and a number of other very talented young (and old!) racers in addition to working at the pro level on occasion (a few times for N2's very own Eziah Davis). My shop's specialty is chassis and suspension and, of course, Pirelli tires.

That said, let's answer some questions you may have.

Exact psi recommendations will vary based on track and conditions and rider preference and pace. In general, I've found that most riders are running fronts too low when left to their own devices or internet or Facebook information. Pirelli offers general guidelines for pressures much in the same way that some suspension tuners will offer you sag numbers; they are often very subjective. I have a few expert racers that are running the fronts as "high" (I put that in quotations because it's only "high" if you are basing your idea of a starting point on an incorrect number) as 38 psi. The answer is (almost) always give the tire (or the suspension, for that matter) what it needs. When riders complain of a motorcycle that's difficult to turn while trail braking, it is usually because they are running an under inflated front tire. The profile of the tire is distorted because it doesn't have enough air in it to maintain the profile under load.

As a general rule of thumb, correct pressures for most track day riders will be 33-36 psi in the front and 24-26 psi in the rear for most compounds on most tracks on most days. Pressures should be set hot (meaning hot on the warmers after 45 minutes to an hour of bake time) at 170-180ºF. Pressures set on the warmers yields a repeatable result. It is worth noting that having an accurate tire gauge is very, very important. Many riders and racers are checking the pressure on a $400 set of tires with a gauge that costs less than their lunch and is about as useful as a ham sandwich when setting pressures. Get a good gauge. Check the gauge you're using now. And checking your pressures is free; do it often. Your tires will thank you.

Compounds have an operating temperature range they are designed to work in. Again, as a general rule, the colder ambient and track temps are, the softer a front and the harder a rear compound you want. In warmer temperatures, a harder front and a softer rear will work better. Pirelli offers fronts in SC1, SC2 and SC3 compounds and rears in SC0, SC1, SC2 and SC3 compounds. We often refer to compounds by colors as well. SC0 is white, SC1 is blue, SC2 is green and SC3 is yellow. A fast rider or racer will almost always want the SC1 or SC0 rear. Slower or more intermediate riders may want to trade the outright grip of the SC1 for the longevity of the SC2 or SC3. Grip and longevity are inversely related; the more grip you have, the quicker the tire will wear out. The less grip you have, the longer the tire will last.

The fronts are a bit more subjective. In general, faster riders will get along better with the SC2 or SC3 fronts while the SC1 front is more of our utility workhorse tire (it can do pretty much anything). Tuning the feel of the front with pressure is very important and there is a lot of overlap in performance and feel. For example, most riders would not be able to tell the difference between an SC1 front run at 36 psi and a SC2 front run at 34 psi. The faster a rider is, the more important it is to isolate which compound and psi gives them the best feel and confidence.

In general, the SBK product is a slightly stiffer carcass when compared to the DOT tire. The siping (or tread) of the tire is a break in surface tension on the DOTs and allows them to deflect more under load than the SBK tires. So, in general, we'll run the DOTs 1psi higher than the SBK. There is a lot of overlap in performance between the fronts and the carcass of the tire can be tuned (within reason) by adjusting pressure without compromising performance and outright grip.

I have attached the official fitment guide as provided by Pirelli which can be used as a general guide and I'll try and monitor the board as best I can and be responsive to questions regarding the tires. We have a variety of compounds and sizes available to suit different riding styles and Pirelli invests a lot of resources in developing the tires and evolving the technology and information we have available to us.

There's a lot more info we can get into regarding warmer usage and compounds and heat cycles and how a tire actually creates heat and things like that, so I'll let you guys decide what you'd like to know and we'll go from there.
 

Attachments

  • 2017 Pirelli RR Fitment guide-4.pdf
    60.1 KB · Views: 183

HondaGalToo

Control Rider
Great info, Mike, thanks!

I'm running the 180/55 rear SC2. Will it still be available? I keep hearing rumors that size is going away. I'd rather not switch to the 180/60, at least not until I need a new chain, as I'll need a couple more links than I currently have to fit that tire. If it's still available, I assume I need to let you know ahead of time, as you probably only stock the way more popular 180/60?
 

MDM

New Member
As of now, there are no plans to discontinue the 180/55 tire and we keep them in stock.

However, I would suggest adding the links to your existing chain and/or replacing that chain to take advantage of the 180/60 V2 tire available. It is a much better tire and made using the new construction method and using the most current SC2 compound.
 

mpusch

Micah
Very helpful baseline, thanks for taking the time to type that out. Looking forward to continuing to understand and use these things better. Liking it so far!
 

HondaGalToo

Control Rider
As of now, there are no plans to discontinue the 180/55 tire and we keep them in stock.

However, I would suggest adding the links to your existing chain and/or replacing that chain to take advantage of the 180/60 V2 tire available. It is a much better tire and made using the new construction method and using the most current SC2 compound.
Thanks for the quick reply! I have enough 180/55s to start off the season. I probably need a new chain/sprockets soon anyway, so I may pull the trigger and try the 180/60. Only issue is adjusting the chain back and forth when/if I use Rosso Corsas or similar for Control Riding, as they'll be 180/55 (I don't think they come in the 180/60).

Anyone using the 180/60s and switching to 180/55s for coaching/rain/whatever, feel free to chime in with tips on how that works for you.
 

MDM

New Member
Thanks for the quick reply! I have enough 180/55s to start off the season. I probably need a new chain/sprockets soon anyway, so I may pull the trigger and try the 180/60. Only issue is adjusting the chain back and forth when/if I use Rosso Corsas or similar for Control Riding, as they'll be 180/55 (I don't think they come in the 180/60).

Anyone using the 180/60s and switching to 180/55s for coaching/rain/whatever, feel free to chime in with tips on how that works for you.

The DRCs are available in the 180/60 as well. Same dimensions as the race spec 180/60.
 

tigerblade

New Member
180/60 SC2 at Heartland Park Topeka yesterday. Apparently the new surface is doing this to a lot of tires. Started at Pirelli's recommended 24 cold/27 hot and dropped to 24 hot per advice at the track. Ran out of time to keep at it. Others said they dropped to 22 hot before it finally cleaned up.

Mike it sounds like SC1 may have fared better?

HPT_Jun2017_06.jpg
 

MDM

New Member
180/60 SC2 at Heartland Park Topeka yesterday. Apparently the new surface is doing this to a lot of tires. Started at Pirelli's recommended 24 cold/27 hot and dropped to 24 hot per advice at the track. Ran out of time to keep at it. Others said they dropped to 22 hot before it finally cleaned up.

Mike it sounds like SC1 may have fared better?

View attachment 4812

I don't have first hand experience at HPT and new surfaces often take a little bit to figure out. Looks to me like that tire is working too hard and overheating.

And we need to be on the same page when talking about "hot pressures". Unless you're getting real time data from the tire on the track or not taking a cool down lap and pulling right off the track and having your pressures checked, what you are calling hot pressures may be an inaccurate number. From the time you see a checkered flag until you get into the pits and put your bike on stands and check pressures, sometimes two or three minutes have elapsed. Maybe more. Data acquisition has showed us that during one lap at Summit Point, the surface temperature of the tire can vary nearly 100ºF.

When I say hot pressures, I mean hot on the warmers. It is constant and repeatable data.

Now consider this, dropping pressures can sometimes yield a different result than what you're looking for and depending on how pressures were being set, it might explain why the tire cleared up at 22psi "hot". When you say "hot" do you mean off the warmers or immediately off the track? Here's why it matters; a tire doesn't necessarily build heat by the the friction of the tire on the track. How it builds heat is by flexing. A tire set at 22psi on the warmers will gain more psi on the track than a tire set at 25psi on the warmers because the tire needs psi to maintain profile. So you may have reduced your starting point, but if that tire gains 4-5 psi on the track (because it is flexing more) and the tire set at 25psi only gains 1psi, you're going to actually be running a higher pressure on track by starting at 22psi. However, how that tire gets to the psi and the temperature of the tire will be very different. Follow?

Again, speculative numbers on my part in regards to that track on my part.

And not knowing all the data, I might be inclined to agree that the SC1 may have been a better choice. It is designed to work in a higher temperature range than the SC2.
 

tigerblade

New Member
And not knowing all the data, I might be inclined to agree that the SC1 may have been a better choice. It is designed to work in a higher temperature range than the SC2.

Going to try an SC1 rear this weekend at Raceway Park of the Midlands. Supposed to be 95 on Saturday.
 

tigerblade

New Member
Hope so. Ran the SC2 for a bit at RPM the week after HPT and the tire cleaned up quite a bit but it was getting pretty squirmy on the gas coming out of the carousel.
 
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