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Ok... I have seen both over the past few days. And I don't have much experiance with cold tearing! From what I have read I hear rebound is the way to resolve cold tearing.

Here are 2 examples of cold tearing .. I think??.. Please shed some light on these. The first pic I know is cold tearing as the tires are on warmers and the PSI for the Perilli slicks are set correct. The second pic look to me to be DOT Mich H2 or S2 rear tires. Might be wrong, but Both bikes are from the same date and time, and the same track VIR. THX! :cool:








 

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superbike2001 said:
Ok... I have seen both over the past few days. And I don't have much experiance with cold tearing! From what I have read I hear rebound is the way to resolve cold tearing.

Here are 2 examples of cold tearing .. I think??.. Please shed some light on these. The first pic I know is cold tearing as the tires are on warmers and the PSI for the Perilli slicks are set correct. The second pic look to me to be DOT Mich H2 or S2 rear tires. Might be wrong, but Both bikes are from the same date and time, and the same track VIR. THX! :cool:






I took out 18 clicks of rebound to fix my problem
 

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Discussion Starter · #3 ·
Rookie said:
superbike2001 said:
Ok... I have seen both over the past few days. And I don't have much experiance with cold tearing! From what I have read I hear rebound is the way to resolve cold tearing.

Here are 2 examples of cold tearing .. I think??.. Please shed some light on these. The first pic I know is cold tearing as the tires are on warmers and the PSI for the Perilli slicks are set correct. The second pic look to me to be DOT Mich H2 or S2 rear tires. Might be wrong, but Both bikes are from the same date and time, and the same track VIR. THX! :cool:





I took out 18 clicks of rebound to fix my problem
I know you did. I would like details. Why and how it occures!
 

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Todd, I thought about something tonight. My tire wear is probably due to a lack of rebound. I am using the shock without the link which would make the spring rate effectively higher, and I should have cranked the rebound up to compensate for that.


I was on H2's and only had the problem with the rear. Mark had the same problem as I did with the rear tire, but he was on Metzlers or Perellis I think.
 

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Try changing the pressure to fix your tearing issues.

You can chase the elusive 'compression' fix for decades and just keep ruining expensive meat.
 

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Alot of times that kind of wear from students of mine is not cold tearing or overheating. Its more often than not someone waiting till the bike is starting to come upright then yanking on the throttle. Smooth is Key.Looking at one of your photos,I can tell you for sure your tire pressure is way too low. Look at the shape of the tire.
 

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pappawheelie said:
Alot of times that kind of wear from students of mine is not cold tearing or overheating. Its more often than not someone waiting till the bike is starting to come upright then yanking on the throttle. Smooth is Key.Looking at one of your photos,I can tell you for sure your tire pressure is way too low. Look at the shape of the tire.
Which one are you talking about being low? The first pic or the second. On the top picture, the front is 3 psi over reccomended and the rear is spot on and the rear had no problems at all.
 

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pappawheelie said:
Alot of times that kind of wear from students of mine is not cold tearing or overheating. Its more often than not someone waiting till the bike is starting to come upright then yanking on the throttle. Smooth is Key.Looking at one of your photos,I can tell you for sure your tire pressure is way too low. Look at the shape of the tire.

Students? What do you teach, kindergarden? :)

There's no way to tell if his pressure is right or wrong from a photo, and it's even harder to see if that's cold tear or just chunking from the shitty Michelins he's running.

"...Someone waiting 'til the bike comes upright then yanking the throttle."

Yeah.. you can tell all that, eh maestro?
 

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pappawheelie said:
Alot of times that kind of wear from students of mine is not cold tearing or overheating. Its more often than not someone waiting till the bike is starting to come upright then yanking on the throttle. Smooth is Key.Looking at one of your photos,I can tell you for sure your tire pressure is way too low. Look at the shape of the tire.
Well, I can tell you the wear is not from improper throttle operation. I don't just whack it open, I roll on smoothly. I ran the same tires at Barber with the same air pressure and had no problems what do ever. Mark (EppyF4i) had the same problem with his rear tire that I did and he was on a different brand. Darin (Rookie) also had the same problem with his front tire and he was on a Pirelli slick.

BTW, I was running 30psi front and rear on my Pilot Race H2's.
 

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Naya the Dingo said:
BTW, I was running 30psi front and rear on my Pilot Race H2's.
Well, there goes the maestro's theory. You're about 6-8 pounds over inflated in the rear for a Pilot Race.

Go figure, huh...
 

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Maestro?No, just saying from experience. Yes Michelin is reccommending way lower tire pressures. Am I a guru,No, Never claimed to be. First better pictures ARE necessary. Lets see a close up of the tire not moving. Can I i tell you what you problem is from looking at a couple of photos, No. Any one that thinks so is an idiot. You could have allot of issues, your bike too. I'm saying from history that I've seen allot of tire wear on the rears solved by throttle control. I've seen allot of fronts fixed by body positioning. I've seen allot fixed with tire pressure. I've seen allot fixed with suspension settings.I've seen wierd wear from alignment issues. Throw it all in a hat and draw a problem, you'll have the same success as asking with those two photos.
 

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900CR said:
Well, there goes the maestro's theory. You're about 6-8 pounds over inflated in the rear for a Pilot Race.

Go figure, huh...
The S2 and H2 tires are last seasons Michelins. They have a different carcass construction than the new Michelin Pilot Race. The H2 rear had the same starting pressure as the M2 rear which I ran more of. I generally ran 28-30 pounds in the rear (Cold).
I do start with 22 PSI cold pressure on the Michelin Pilot Powers.


Tire wear; If you aren't running warmers you need to take it easier for the first 1.5 laps, you could really put the hurtin on a tire in that time. If you are running warmers you can generally give it hell right out of the pits, no problems.
I would say this probably is a "rebound issue". I can't tell you "more or less" to solve it, but I can make a good suggestion.
Go run 3 laps on your current setting, look at the tire. Add two clicks of rebound damping, run 3 laps and look at the tire. Take out 4 clicks of rebound (now -2 from original), run 3 laps, look at tire. One of these setting will likely clean up some of the cold tearing. You didn't adjust the suspension a whole lot from original, likely it will feel better. If it feels worse but wears better you are going to need to talk to a suspension guy.
Check your guage against the Michelin mans the next time he is at the track, ask him about sugested pressures too. Guages can be suprisingly off and that can make a big difference (especially on this years model tires).
Good luck, dial it in and it will wear better.
Hoov.
 

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I agree with Hoove also as I had this same problem with my slicks. I was tearing them up in one day. I actually had to bump up the compression after messing with the rebound until it was unridable.. My problem was I was hard on the gas in the corners and the suspension was compressing and not returning until after I was out of the turn. Once the suspension is compressed the tire has no real suspension left and the tire will skip causing it to look like its tearing. Hope this helps. But I would first work with the rebound.
 

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Try comp, not rebound.

Not sure how fast you guys are, but making a 4 click change to rebound will land anyone with any talent right on their ass.

Problem with chasing all your fancy internet suspension settings is that there are usually only one or two settings that work for a given track. Now what do you do when the tire starts tearing? Mess up the suspension so the bike is unsafe/unpredicatable? Nope. It's tearing because it's not reaching operating tempurature deep enough in the compound.... let the tire tell you what to do.

We've been all over the map with tearing issues at Thunderhill through 3 models of Dunlops. What's worked is reducing the tire pressures while tightening up the compound. So you'd think you'd want a softer compound, right? Nope. 902's have fit the bill all summer, only starting to tear if pressures are run over 28-29Lbs.

Michelin's seem to just chunk, and when they tear, it's brutal. It's also not safe to run a tearing tire, as you're not doing anything but ripping the compound off the carcass. It will go off quickly if you keep running it... ask me how I know.

Again, if you're just out for a track cruise, do whatever you guys do... no worries. If you want to get faster, chase the problem at the source.

BTW, sorry i'm not up to speed on last year's track tires. Wish I had a set that would last that long. Tell me your secret.
 

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superbike2001 said:
Ok... I have seen both over the past few days. And I don't have much experiance with cold tearing! From what I have read I hear rebound is the way to resolve cold tearing.

Here are 2 examples of cold tearing .. I think??.. Please shed some light on these. The first pic I know is cold tearing as the tires are on warmers and the PSI for the Perilli slicks are set correct. The second pic look to me to be DOT Mich H2 or S2 rear tires. Might be wrong, but Both bikes are from the same date and time, and the same track VIR. THX! :cool:








Can't tell a thing from the pics per tires tearing or balling. Two different machines/riders and two different brands of tires. What have you done so far to eliminate the tearing?

I do know this; warmers are not always the answer. Different brands require different warming, ie; Dunlops require warmers at 170 for 35-45 minutes or so. This is much longer duration and warmer than Mich. OR Pirelli. In order to get the info. you need, for the right direction to go, you need to donate more info.. I haven't run VIR's surface, that's another variable to consider, smooth or rough? Some tracks surfaces are disastrous on tires while others are kind.
 
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