Interesting Hoosier problem
10-16-2011, 05:56 PM
#16
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Thread Starter
I think the highest pressures I saw were around 46 and I felt like the rear was loose.
10-16-2011, 06:37 PM
#17
Yes, if your car is particularly heavy. Hoosiers like to be run hard, but the problem is that at the pressure that they run best, you only have another pound or so increase before they get greasy, so most guys seem run them well below the optimum because of that.
On my 2700 lb RSA they worked best around 38 lbs hot.
On my 2700 lb RSA they worked best around 38 lbs hot.
There is a larger sweet spot that the tires run with a lower pressure, although this is NOT the fastest pressure setting for the tire. The downside to the higher pressure is it will go from "Oh my god awesome stick" to "Oh F*&% it's slippery and the tires are gone" . Point here is that for many people the lower pressure setting and thus larger sweet spot may be a better setting for many people, although then you run the risk of damaging the tire (sidewall or bead) to an improper over loading of weight, which is what I believe is what you are seeing.
I've found the best (fastest) pressure to be 39psi hot on a HoosierA6 & R6, (Hoosier slicks require totally different pressures).
With that being said ..... Your pressures will vary between guages, it's very possible that Larry's 38 hot psi on his guage is the exact same as the 39 hot psi on my guage. Point being that you need to find what works best for you and ALWAYS use the same guage and conditions. You might try Nitrogen as it makes for more consistency and less change due to moisture content in the tire.
I'm not a tire engineer, just a good ole boy with a little experience over the years.
10-17-2011, 09:33 AM
#18
Mr. Excitement
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I can understand talking about heat and pressures if this were a sidewall or tread area failure. This looks like a bead wire failure. The bead is not flexed while in use on the tire rim. Why would the bead wire fail from stress before the side wall or tread belting? As said it is the one part of a tire that is not being flexed.
10-17-2011, 01:27 PM
#19
I can understand talking about heat and pressures if this were a sidewall or tread area failure. This looks like a bead wire failure. The bead is not flexed while in use on the tire rim. Why would the bead wire fail from stress before the side wall or tread belting? As said it is the one part of a tire that is not being flexed.
It's also not just the stresses but on the tires when cornering but when braking also, especially with a tire as sticky as the Hoosiers.
10-17-2011, 01:29 PM
#20
I can understand talking about heat and pressures if this were a sidewall or tread area failure. This looks like a bead wire failure. The bead is not flexed while in use on the tire rim. Why would the bead wire fail from stress before the side wall or tread belting? As said it is the one part of a tire that is not being flexed.
10-17-2011, 02:37 PM
#21
Mr. Excitement
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Nor am I, so I ask questions in order to learm me someting now and then. This one has my attention. I am having a hard time figuring out how the Bead which is held tightly and inflexably in place on the rim can fail and not along with the sidewall or belting. The bead is not stressed or heated to the same temps as the sidewall would be. Rotor heat cooking the rim and tire is one non tire heat source but there would be other signs of that. I found the tire temps to be lowest near the rim itself (Yes I have geeked out and checked all around the tire a time or two) with the rim acting as a heat sink. Less heat less flexation but still failed? I might be led to think there was as build issue. Any failures of this type in other brands?
10-17-2011, 02:46 PM
#22
Mr. Excitement
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That happened to Mike Bavaro at Thunderbolt. That same looking wire was sticking out of the sidewall. I thought that it might have been some sort of tie wire because it looks too fat to be part of the bead wiring from what I have seen. I'd be interested to know what you find out. I also have a few dead Hoosiers around here. Maybe it's time to take a sawzall to one. 
10-17-2011, 02:52 PM
#23
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I had this same problem. I clipped it off when I noticed it and kept running. I clipped probably 2 feet
out over the day. The rate it came out was manageable, but the last run, it crept out 6" and took out
some paint on my rear fender. It's has to be one of the bead wires for that much to come out.
I figure this was an isolated incident. Guess not.
Edit: I wonder if the bead wire weld is brittle and faulty.
out over the day. The rate it came out was manageable, but the last run, it crept out 6" and took out
some paint on my rear fender. It's has to be one of the bead wires for that much to come out.
I figure this was an isolated incident. Guess not.
Edit: I wonder if the bead wire weld is brittle and faulty.
10-18-2011, 04:14 PM
#25
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Just to clarify, which particular Hoosiers are these? A6/R6 or R80/R100s? Or is it happening across the board?
10-18-2011, 04:26 PM
#26
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10-18-2011, 05:20 PM
#27
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Dave, I also endorse high 30's for the R6. On the RS I found them best at 38F 39R hot. Your car weighs about 400 lbs more ......
10-19-2011, 08:46 AM
#28
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Have seen it on my customers cars with R6 and with R80/100 (slicks). The slicks seemed to be more common with this issue. No reason we could find other than manufacturer defect. Seemed it happened one tire about every 10 sets. Never seen it happen on a front, just the rears.
