have R7's changed? disturbing grooving
09-26-2018, 04:12 PM
#121
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No question about the body of your comment. yes, the driver influences a lot, BUT , there are indications of set up, overall wear and issues that can be seen by tire tread outside, or penetrating temps, regardless of when you get them. sure, you can capture the actual data from the tire with active IR sensors, OR you can get hot pit temps, OR you can even get paddock readings. pressure do NOT change very fast , in fact you have about 10mins before you see any noticeable changes. (ive tested this with a timer vs pressure gauge to show this is true). yes, temps fall off quickly at first and then stabilize. the tire doesnt "equalize " across the tread as they sit.... try testing that at the track and you will see that the spread actually stays pretty close to intact, when comparing a hot pit temp (eg 200f, 190f 180f vs in the paddock that might be 170f, 160f 150f after traveling to your parking spot. the point here is the information is very useful , you just need to know what the tire is telling you and there is a lot of averaging in the hot pit that is near the same in the paddock and does not represent any particular part of the track where all the numbers can change.
09-26-2018, 06:01 PM
#123
Rennlist Member
Paddock readings are near uselsss in my experience, but I'm not up for an argument. If you think that is good, then go for it. You're statement about pressures is completely wrong based on everything I've ever seen and against what the best chassis and tire engineers I've seen and worked with would tell you. Good luck.
as far as paddock reading, you migh have misunderstood . the spread is what we care about, can we agree on that. because of the thermal characteristics of rubber, it is pretty easy to show that a taking temps , in 3 positions, (outer, mid and inner) shows a temp spread that stays relatively in tact even after a minute or two after driving from track to a paddock space vs taking it in the hot pits. Sure, the temps will fall so peak temperature measurements are invalid...... but air pressure and spread are "good enough" for many of the factors that influence the temp spread.
below is a tire, set at 23psi cold, this is coming into the paddock and immediately taking temps and pressures. as you can see, in 3-4 mins, pressures dont change much to be detected by an analog gauge.
09-27-2018, 08:07 PM
#125
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09-27-2018, 08:11 PM
#126
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I have both on my A7's. The slice looking issue and the dull separation looking issue. It's at Goldcrest right now, but the tires only have one 3 lap TT session on them. Car is 3300 lbs w/ driver 996 TT.
09-27-2018, 08:16 PM
#127
Rennlist Member
what i want to know, is how those "wires" were sticking out the side of the tire. how is that even possible?
09-28-2018, 04:19 PM
#128
Rennlist Member
Agree w/OP comments on what appears to be the shoulder seams. Tried 20" 265/335 combo recently and experienced visible seam line even having read this first and using higher pressures. Not a rubbing or alignment issue. Didn't get the splits except minor depth on first stint cooler. Ramped up semi carefully. Were fine rest of day but slower at higher recommended pressures. Definitely not the same pressure flexibility range as the R6s. The narrow 335 is getting reworked to be proper width and needs it.
09-28-2018, 07:25 PM
#129
I wish the OP or someone would report back Hoosier's opinion. I was thinking about what Mark said about the wire poking out too. Hoosiers are fast tires but they are not made well and/or they are thin and light. I have seen many hoosier defects like ballon sidewalls (feesl like tire out of balance) , massive bead flash (makes tires leak air), exposed metal cord on bead, metal wires poke out tire, and now these "cold tears."
As a group we have run hoosiers forever. These are not new to use and we never saw cold tears before. And this is the 1st I have seen since the new "7" formulation. I suspect Hoosier is doing something different in manufacture and they need to be told!
I mount my own tires. Mounting tires is hard work. Those 19 y/o buff tire monkeys make it look easy but it isn't. Lots of force is used. I try to use finesse and minimal force. Even in Cali we are getting 60 degree mornings over the last 6 months and colder before April. Stiff tires need much more force to mount. The new tire machines can rip a tire in half. Because Hoosiers are poorly made tires I wonder if it is at all possible that tire mounting is the problem? Is it possible that the thin light hoosier tire is getting killed by the tire machine? You can full on dragster style wrinkle the sidewall of a hoosier with the shoe of my tire machine. I have done that by accident a a rookie tire mounter. I think about how that wire can poke through. If the bead is damaged during mounting the cable of wires in the bead, one wire can break. That wire would cut its way through the tire upon being put in service and then we see the wire poke through the tire and cut bodywork etc. It becomes like that one wire broken wire poking out of your winch cable.
I have an air driven Hunter machine that needs 125psi nominal. May compressor puts out 100psi at best. So I can't put out 100% of the force to break, place, and seat beads. I can hook up to nitrogen tank but that costs me money. So I cheat! When I mount my tires I leave them sit in the sun and that softens the rubber. I feel like I use 80% of the energy to mount the tire when it is hot and 100psi is then more than plenty. I never have these cold tear or wires poke out issues and I use very low tire pressures. Perhaps tire mounting is part of the problem?
As a group we have run hoosiers forever. These are not new to use and we never saw cold tears before. And this is the 1st I have seen since the new "7" formulation. I suspect Hoosier is doing something different in manufacture and they need to be told!
I mount my own tires. Mounting tires is hard work. Those 19 y/o buff tire monkeys make it look easy but it isn't. Lots of force is used. I try to use finesse and minimal force. Even in Cali we are getting 60 degree mornings over the last 6 months and colder before April. Stiff tires need much more force to mount. The new tire machines can rip a tire in half. Because Hoosiers are poorly made tires I wonder if it is at all possible that tire mounting is the problem? Is it possible that the thin light hoosier tire is getting killed by the tire machine? You can full on dragster style wrinkle the sidewall of a hoosier with the shoe of my tire machine. I have done that by accident a a rookie tire mounter. I think about how that wire can poke through. If the bead is damaged during mounting the cable of wires in the bead, one wire can break. That wire would cut its way through the tire upon being put in service and then we see the wire poke through the tire and cut bodywork etc. It becomes like that one wire broken wire poking out of your winch cable.
I have an air driven Hunter machine that needs 125psi nominal. May compressor puts out 100psi at best. So I can't put out 100% of the force to break, place, and seat beads. I can hook up to nitrogen tank but that costs me money. So I cheat! When I mount my tires I leave them sit in the sun and that softens the rubber. I feel like I use 80% of the energy to mount the tire when it is hot and 100psi is then more than plenty. I never have these cold tear or wires poke out issues and I use very low tire pressures. Perhaps tire mounting is part of the problem?
09-28-2018, 08:11 PM
#130
Rennlist Member
I was thinking about the mounting of the tires being the issue as well. i always cringe watching the guys wrench on my rims and tires. doesnt take much to do damage. and yes, it will be interesting to hear what hoosier comes back with.
I wish the OP or someone would report back Hoosier's opinion. I was thinking about what Mark said about the wire poking out too. Hoosiers are fast tires but they are not made well and/or they are thin and light. I have seen many hoosier defects like ballon sidewalls (feesl like tire out of balance) , massive bead flash (makes tires leak air), exposed metal cord on bead, metal wires poke out tire, and now these "cold tears."
As a group we have run hoosiers forever. These are not new to use and we never saw cold tears before. And this is the 1st I have seen since the new "7" formulation. I suspect Hoosier is doing something different in manufacture and they need to be told!
I mount my own tires. Mounting tires is hard work. Those 19 y/o buff tire monkeys make it look easy but it isn't. Lots of force is used. I try to use finesse and minimal force. Even in Cali we are getting 60 degree mornings over the last 6 months and colder before April. Stiff tires need much more force to mount. The new tire machines can rip a tire in half. Because Hoosiers are poorly made tires I wonder if it is at all possible that tire mounting is the problem? Is it possible that the thin light hoosier tire is getting killed by the tire machine? You can full on dragster style wrinkle the sidewall of a hoosier with the shoe of my tire machine. I have done that by accident a a rookie tire mounter. I think about how that wire can poke through. If the bead is damaged during mounting the cable of wires in the bead, one wire can break. That wire would cut its way through the tire upon being put in service and then we see the wire poke through the tire and cut bodywork etc. It becomes like that one wire broken wire poking out of your winch cable.
I have an air driven Hunter machine that needs 125psi nominal. May compressor puts out 100psi at best. So I can't put out 100% of the force to break, place, and seat beads. I can hook up to nitrogen tank but that costs me money. So I cheat! When I mount my tires I leave them sit in the sun and that softens the rubber. I feel like I use 80% of the energy to mount the tire when it is hot and 100psi is then more than plenty. I never have these cold tear or wires poke out issues and I use very low tire pressures. Perhaps tire mounting is part of the problem?
As a group we have run hoosiers forever. These are not new to use and we never saw cold tears before. And this is the 1st I have seen since the new "7" formulation. I suspect Hoosier is doing something different in manufacture and they need to be told!
I mount my own tires. Mounting tires is hard work. Those 19 y/o buff tire monkeys make it look easy but it isn't. Lots of force is used. I try to use finesse and minimal force. Even in Cali we are getting 60 degree mornings over the last 6 months and colder before April. Stiff tires need much more force to mount. The new tire machines can rip a tire in half. Because Hoosiers are poorly made tires I wonder if it is at all possible that tire mounting is the problem? Is it possible that the thin light hoosier tire is getting killed by the tire machine? You can full on dragster style wrinkle the sidewall of a hoosier with the shoe of my tire machine. I have done that by accident a a rookie tire mounter. I think about how that wire can poke through. If the bead is damaged during mounting the cable of wires in the bead, one wire can break. That wire would cut its way through the tire upon being put in service and then we see the wire poke through the tire and cut bodywork etc. It becomes like that one wire broken wire poking out of your winch cable.
I have an air driven Hunter machine that needs 125psi nominal. May compressor puts out 100psi at best. So I can't put out 100% of the force to break, place, and seat beads. I can hook up to nitrogen tank but that costs me money. So I cheat! When I mount my tires I leave them sit in the sun and that softens the rubber. I feel like I use 80% of the energy to mount the tire when it is hot and 100psi is then more than plenty. I never have these cold tear or wires poke out issues and I use very low tire pressures. Perhaps tire mounting is part of the problem?
09-28-2018, 09:35 PM
#131
Rennlist Member
For what it's worth I've always used a senior tech at my shop for years, never had a problem w Hoosiers. Must say the vette 345 runflats were a challenge, they use to get a group of guys for those initially.
09-28-2018, 10:02 PM
#132
Yes! And now the new machine have a depressor disc that focuses the mounting pressure right where the cold tears are showing up. Is that a coincidence? I still have an older machine that uses a single mounting shoe. It takes more finesse to use the older machines.
09-29-2018, 01:38 AM
#133
Rennlist Member
Getting R7s pulled next week, will look at bead areas, equipment, and ask shop for comments. Hopefully we will all get some answers/resolution before next season, arrrg.
09-29-2018, 11:09 PM
#134
Rennlist Member
I wish the OP or someone would report back Hoosier's opinion. I was thinking about what Mark said about the wire poking out too. Hoosiers are fast tires but they are not made well and/or they are thin and light. I have seen many hoosier defects like ballon sidewalls (feesl like tire out of balance) , massive bead flash (makes tires leak air), exposed metal cord on bead, metal wires poke out tire, and now these "cold tears."
As a group we have run hoosiers forever. These are not new to use and we never saw cold tears before. And this is the 1st I have seen since the new "7" formulation. I suspect Hoosier is doing something different in manufacture and they need to be told!
I mount my own tires. Mounting tires is hard work. Those 19 y/o buff tire monkeys make it look easy but it isn't. Lots of force is used. I try to use finesse and minimal force. Even in Cali we are getting 60 degree mornings over the last 6 months and colder before April. Stiff tires need much more force to mount. The new tire machines can rip a tire in half. Because Hoosiers are poorly made tires I wonder if it is at all possible that tire mounting is the problem? Is it possible that the thin light hoosier tire is getting killed by the tire machine? You can full on dragster style wrinkle the sidewall of a hoosier with the shoe of my tire machine. I have done that by accident a a rookie tire mounter. I think about how that wire can poke through. If the bead is damaged during mounting the cable of wires in the bead, one wire can break. That wire would cut its way through the tire upon being put in service and then we see the wire poke through the tire and cut bodywork etc. It becomes like that one wire broken wire poking out of your winch cable.
I have an air driven Hunter machine that needs 125psi nominal. May compressor puts out 100psi at best. So I can't put out 100% of the force to break, place, and seat beads. I can hook up to nitrogen tank but that costs me money. So I cheat! When I mount my tires I leave them sit in the sun and that softens the rubber. I feel like I use 80% of the energy to mount the tire when it is hot and 100psi is then more than plenty. I never have these cold tear or wires poke out issues and I use very low tire pressures. Perhaps tire mounting is part of the problem?
As a group we have run hoosiers forever. These are not new to use and we never saw cold tears before. And this is the 1st I have seen since the new "7" formulation. I suspect Hoosier is doing something different in manufacture and they need to be told!
I mount my own tires. Mounting tires is hard work. Those 19 y/o buff tire monkeys make it look easy but it isn't. Lots of force is used. I try to use finesse and minimal force. Even in Cali we are getting 60 degree mornings over the last 6 months and colder before April. Stiff tires need much more force to mount. The new tire machines can rip a tire in half. Because Hoosiers are poorly made tires I wonder if it is at all possible that tire mounting is the problem? Is it possible that the thin light hoosier tire is getting killed by the tire machine? You can full on dragster style wrinkle the sidewall of a hoosier with the shoe of my tire machine. I have done that by accident a a rookie tire mounter. I think about how that wire can poke through. If the bead is damaged during mounting the cable of wires in the bead, one wire can break. That wire would cut its way through the tire upon being put in service and then we see the wire poke through the tire and cut bodywork etc. It becomes like that one wire broken wire poking out of your winch cable.
I have an air driven Hunter machine that needs 125psi nominal. May compressor puts out 100psi at best. So I can't put out 100% of the force to break, place, and seat beads. I can hook up to nitrogen tank but that costs me money. So I cheat! When I mount my tires I leave them sit in the sun and that softens the rubber. I feel like I use 80% of the energy to mount the tire when it is hot and 100psi is then more than plenty. I never have these cold tear or wires poke out issues and I use very low tire pressures. Perhaps tire mounting is part of the problem?
10-01-2018, 02:46 AM
#135
Rennlist Member
I run the 315 tire. always start at 32 psi and cut my first session short to bleed down to 37-38 where they stay throughout the day. This is on a 996 GT3. My tires, at 38 psi, on my GT3 will allow the car to run 1:58 at WGI. I typically get 32-36 HC out of a set of Hoosiers and never have seen these wear pattern's.
And yes, I have seen a 14 psi change in a tire running at WGI before.
And yes, I have seen a 14 psi change in a tire running at WGI before.
Too bad another Kiborked thread wasting so much time reading drivel. Hope he goes on his meds soon.
Ive been doing it wrong trying to stay under 32 and that makes me start under 20 because I don’t want to stop and waste laps to get out and bleed down.
Starting to low contributes to overheating and the damage in OP pics perhaps.
I have had the same.
I can’t get 16 sessions out of the tires and they are completely cooked anyway from overheating once I get them 32+. Perhaps better to run higher and manage the tires better.
I plan to deal with the tires going off as opposed to give up the first 3 laps to get them up carefully.
Going out at 26 will make me come in on lap 4 to bring them back down to 32 and maybe I can run them higher because then they don’t overheat as much?
Last edited by TRAKCAR; 10-01-2018 at 03:14 AM.