Spartan

Thanks Bill. Now I can say that I drove the tires off the car!!

Veloce Raptor

Viking, all i know os that there have been an alarming number of these identical failures since their "strategic partnership" began.

onefastviking

What types of cars have you observed it on ? All heavy and/or big hp ?

I have seen a number of failures obviously due to alignment, improper set up, and pressure, but we see that in all tires from time to time.
This tread separating from the sidewall is a little different than those. How many of these tread separating at sidewalls have you seen ?

Veloce Raptor

No, not all heavy and or high HP.

A lot. At a variety of tracks.

onefastviking

Well have you seen any common point ? And how do you explain how some people are having repeated problems with the tire and issue, and yet other people having zero issues with them ? If there were an issue in manufacture, or design change, you would think it would be spread even amongst all users, not repeated with one and zero with another.

Would you consider the failure jakermc had at TWS in the 996 the same type of failure as this OP has had ?

onefastviking

Here is a bulletin from Hoosier which I think describes a number of the reasons why some people see many failures and others see none.

http://www.hoosiertire.com/pbP28518.HTM

I did recently have an incident where a driver reported hitting an apex curb pretty hard and then a vibration started. Upon close inspection all seemed ok, upon spinning the wheel/tire on a balancer the wheel was found to be straight but the tire experienced a internal separation that was not yet obvious and I suspect if it had continued to be used it would have separated at the tread/sidewall.

Veloce Raptor

Not sure how to explain it. I have seen a lot of treat separation cases, dunno why. I like the tires a lot, but this makes me very leery.

Jakermc was more excessive and extremely rapid wear.

I believe that bulletin reflects the R6, not the R80/R100.

onefastviking

I agree 100% on jakermc's issue, that's why I asked, plus it was one that I remember us both looking at and discussing.

Also agree that the bulletin reflects the DOT's , although it really never specified R6/A6, or otherwise.
I do also believe though that the issues discussed in that bulletin may very well be the same issues occuring in the slicks.
It's also a valid point to make, in the bulletin and discussing here on RL, that some of the qualities we know and love with the Hoosier tires such as light weight of tires, and super sticky (soft) compound, could contribute to the issues of a tire failing when hit a curb or run too low on pressure for the load being put into the tire thus damaging the tire to have a subsequent failure.

I believe, just my opinion, that when loaded properly, set up properly, and ran properly, you won't have any issues more than any other brand of tire. Which is why I believe some people have non-existent issues with the Hoosiers, and others have repeated failures.

For me, the results speak for themselves and Hoosier's are the tire !
It's hard to argue with repeated wins and consistent track records set and re-set. - But of course it's not JUST the tire that produces that, but it is a very important part of the whole package since it's what puts the power to the ground and gets us around the corners in a hurry.

KaiB

It's my opinion that you have a deal with Hoosier.

You've been running their new proto R(GTZ+)9 compound, branded as a R6 and with the DOT grooves cut into the carcass.

Lap times about 1.5s faster than new A6's and longevity of the BFG R1 on a hot track is what I'm told.

When are you going to let the cat out of the bag and when is Hoosier going to release the tire to the general race public?

Huh? Out with it!

Matt Romanowski

I think you have it right here. Like they say, load capacity is directly related to air volume. Porsches in general transfer weight reward much better than any other car, so they put way more load in the rear tires. This makes tire selection, car setup, and air pressures much more important. So you get a car that is set up slightly wrong, who is transfering tons of weight (new cars are way too heavy) and they kill tires. Same reason that people blow tires at Daytona.

onefastviking

Nice try Kai, I wish I had some super secret new compound, but Roger Penske I am not. You should have been at the NASA Hallett event to see what tire we did have on our cars.
I have used in the past the old Goodyear GS-C race tire, back some 6-7 years ago, even reconsidered it when they decided to come back into the race car tire business again. Also have run Kumho's, Toyo, Nitto, BFG's, Avon, Yokohama's, and even Michelin. I'm out to get top results and win, to do that I'm running Hoosier's, no other reasons. When someone builds a better, faster, tire for my current race applications you will see me on that tire.
Interestingly enough, we have a test and tune set up to compare some tires over the summer to make sure we are on the fastest possible tire that we can be. It's a never ending search to run faster than we did last time out.

onefastviking

Yep !
One other thought I'll share just to get yours and others opinions, it's kind of a far out there thought but I try to think outside the box and these are the results.
Could the pendulum effect of the heavy engine being in the rear combined with some movement in the stock style rubber engine mounts allow more of a greater say peak load to the outside tire at just the moment it is really stretching the tread away from the sidewall enough to cause a stretching of the ply's and then resulting in a subsequent failure ?
Of course it would take the right combination of load, low pressure, weak or rubber mounts, hard cornering, etc, etc, to still produce this in my opinion. But it could be a contributing factor in my crazy little mind.

onefastviking

Here is another point found, and quoted from, the Ferrari Chat - Challenge cars board, regarding the same issues we are discussing here.

http://ferrarichat.com/forum/showthread.php?p=140952775

or for ease just read the quote below.

"This is caused by low tire pressure. Excessive camber will aggrevate it. The damage usually occurs in the first 1-2 laps as at low pressure the wheel will pinch the sidewall and cause a cut on the interior of the tire. It may take 8-10 laps for the damage and failure to become apparent. If you are starting bellow 22 psi you are taking a huge risk regardless of Hoosier or Perelli tires. Drivers must be extremely carefull on their out laps to avoid excessive load on the tires, avoid any curbing and keep speeds down on high bank corners. this is a know issue with any of the low profile slick tires started at low pressure and high camber angles. "

jrgordonsenior

Viking I mentioned in a different thread last week that I had my outsider rear Yoko go down on me at the end of the first hot lap in a race at Buttonwillow. I was using a brand new set of Yoko slicks and started that outside rear at 20 cold. That's never happened to me before but what was different was that these tires were new and of course dead cold. I always qualify on fresh tires first at 24-25 lbs and although they cool down they're still retaining some heat and a cycle. I was definitely racing and ran over some low curbs but it went down on a slow 2nd gear turn as I was turning in. I immediately went off into soft dirt and the tire's just fine. Expensive lesson learned....

onefastviking

Thank you JR, that's all I am trying to do here, save some people from some really expensive lessons, by learning thru other people's experiences.