did I overheat tires?, rubber migration on A7 |
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did I overheat tires?, rubber migration on A7 |
mskala |
Oct 13 2016, 06:42 PM
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#1
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R Group: Members Posts: 1,925 Joined: 2-January 03 From: Massachusetts Member No.: 79 Region Association: None |
This is what both my rears looked like after last weekend auto-x. It wasn't
even hot outside. Is this an indicator of anything particular I'm doing wrong? About the only abnormal thing on the course was a long 180 that was not quite a hairpin but I had the gas pedal to the floor for the whole last half of it. Basically with a 2.3 and limited slip and my setup, no possible way to spin with foot on the floor. |
wndsrfr |
Oct 13 2016, 07:25 PM
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#2
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Senior Member Group: Members Posts: 1,428 Joined: 30-April 09 From: Rescue, Virginia Member No.: 10,318 Region Association: MidAtlantic Region |
Nothin' wrong with that tire.....they will shed a little bit of rubber that forms "worms" & they'll migrate to where your camber allows them to hang on. I see this all the time on my track tires. Drive it like you stole it! (IMG:style_emoticons/default/driving.gif)
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ChrisFoley |
Oct 14 2016, 06:35 AM
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#3
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I am Tangerine Racing Group: Members Posts: 7,920 Joined: 29-January 03 From: Bolton, CT Member No.: 209 Region Association: None |
That's normal for a soft tire that was working hard.
If it bothers you, scrape it off between events. (he says, knowing how difficult that is) |
mskala |
Oct 14 2016, 09:20 AM
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#4
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R Group: Members Posts: 1,925 Joined: 2-January 03 From: Massachusetts Member No.: 79 Region Association: None |
yeah, thanks guys but I don't have a tool that's going to get that off without
a large amount of effort. |
Cracker |
Oct 14 2016, 09:44 AM
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#5
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Advanced Member Group: Members Posts: 2,148 Joined: 2-February 10 From: Atlanta (area) Member No.: 11,316 Region Association: South East States |
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sixaddict |
Oct 14 2016, 11:43 AM
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#6
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Senior Member Group: Members Posts: 800 Joined: 22-January 09 From: Panama City Beach, FL Member No.: 9,961 Region Association: South East States |
That's exactly what you spent all that money for....Akin to music to my ears! (IMG:style_emoticons/default/evilgrin.gif)
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Eddie914 |
Oct 15 2016, 06:05 PM
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#7
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Unregistered |
Overheating is apparent when the rubber starts turning blue ... BTDT (IMG:style_emoticons/default/sad.gif)
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ottox914 |
Oct 26 2016, 10:59 AM
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#8
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The glory that once was. Group: Members Posts: 1,302 Joined: 15-December 03 From: Mahtomedi, MN Member No.: 1,438 Region Association: Upper MidWest |
Could be rubber "worms" migrating off your tires. Some of that could be OPR. Other Peoples Rubber, their worms that detached and were on track. Your stickies picked it up. There are some battery powered, and corded scrapers you can use to peal/cut that crud off if you need to. Or as others have said, drive it like you stole it. First time I saw that on my auto-x tires I paniced- I spent HOW much for these tires and they're defective?!?!??! Some more experienced guys laughed a little and explained how it all worked. No big dealio. Go fast. Have fun.
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mskala |
Oct 26 2016, 12:39 PM
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#9
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R Group: Members Posts: 1,925 Joined: 2-January 03 From: Massachusetts Member No.: 79 Region Association: None |
Yeah, I actually found that the 'adhesive remover' blade for the vibrating saw tool
thing gets the excess rubber off pretty easily. So, my tires aren't blue or ridiculously worn after 5 events (8-9 runs avg). However, at the last event we did 6 in the morning and 6 again in the afternoon. By the 5th and 6th runs the car felt really sloppy and even though I was driving a better line it was slower. Not 'overheating' but out of the good grip temp range of the 'A' compound. So, IMO the A7 is inferior to the A6 where I never noticed this. Either I should go to the R7 or find something else maybe. Anybody looking for a good deal on used 205-45-16? |
6freak |
Oct 26 2016, 02:34 PM
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#10
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MR.C Group: Members Posts: 4,740 Joined: 19-March 08 From: Tacoma WA Member No.: 8,829 Region Association: Pacific Northwest |
Overheating is apparent when the rubber starts turning blue ... BTDT (IMG:style_emoticons/default/sad.gif) What you see is normal! thier AX tires not track tires correct ? I use Kumho and dont know much about the Hoosiers,or if you even have a choice with them... no wheel spin means your not pushing it hard enough hahahah have fun MikeC ive seen lotsa blue tires Eddie |
mskala |
Oct 26 2016, 08:19 PM
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#11
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R Group: Members Posts: 1,925 Joined: 2-January 03 From: Massachusetts Member No.: 79 Region Association: None |
I can't deal with tires that get worse after the 4th run on a mild day. I'm
probably going to have a co-driver next season too. I might be able to use the R7, or go down to bridgestone re-71r. |
ottox914 |
Oct 27 2016, 10:52 AM
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#12
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The glory that once was. Group: Members Posts: 1,302 Joined: 15-December 03 From: Mahtomedi, MN Member No.: 1,438 Region Association: Upper MidWest |
Do you have a pyrometer to check temps of the rubber? Hoosier can give you a temp range where those tires will stay happy. Maybe you and your co-driver just need to check temps after each run when you check pressures, and have a basic garden sprayer handy to chill things down. Insulated tire covers can be helpful too- you can make your own, black on one side to grab and hold heat on cold days, silver reflective on the other to keep heat out on the warmer days. Think the material used for windsheld sun shades you can buy at walmart. And don't let them freeze over the winter. Put them in your basement, best to be wrapped in that cling plastic you can get on rolls.
I'd hate to see you go to a less effective tire if there were ways to make these work better for you. |
Randal |
Oct 27 2016, 01:02 PM
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#13
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Advanced Member Group: Members Posts: 4,446 Joined: 29-May 03 From: Los Altos, CA Member No.: 750 |
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ChrisFoley |
Oct 27 2016, 01:20 PM
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#14
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I am Tangerine Racing Group: Members Posts: 7,920 Joined: 29-January 03 From: Bolton, CT Member No.: 209 Region Association: None |
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mskala |
Oct 27 2016, 03:02 PM
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#15
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R Group: Members Posts: 1,925 Joined: 2-January 03 From: Massachusetts Member No.: 79 Region Association: None |
I never use the water sprayer, but tried a friend's once I was feeling the heat in the
tire that last day. It really didn't do anything. I actually don't have enough room in the wheel well to insert it well. It was a relatively cool day, so I think I would be in trouble in the middle of summer. Do you have a pyrometer to check temps of the rubber? Hoosier can give you a temp range where those tires will stay happy. Maybe you and your co-driver just need to check temps after each run when you check pressures, and have a basic garden sprayer handy to chill things down. Insulated tire covers can be helpful too- you can make your own, black on one side to grab and hold heat on cold days, silver reflective on the other to keep heat out on the warmer days. Think the material used for windsheld sun shades you can buy at walmart. And don't let them freeze over the winter. Put them in your basement, best to be wrapped in that cling plastic you can get on rolls. I'd hate to see you go to a less effective tire if there were ways to make these work better for you. |
6freak |
Oct 27 2016, 03:20 PM
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#16
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MR.C Group: Members Posts: 4,740 Joined: 19-March 08 From: Tacoma WA Member No.: 8,829 Region Association: Pacific Northwest |
By the 5th and 6th runs the car felt really sloppy and even though I was driving a better line it was slower. Not 'overheating' but out of the good grip temp range of the 'A' compound. Tire pressure. yep building heat/pressure fast with AX tires and not checking pressures after every run will make basketballs outta them! even on a cool day.... |
mskala |
Oct 27 2016, 04:20 PM
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#17
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R Group: Members Posts: 1,925 Joined: 2-January 03 From: Massachusetts Member No.: 79 Region Association: None |
I check pressure after every run and reduce back to my 'target'.
By the 5th and 6th runs the car felt really sloppy and even though I was driving a better line it was slower. Not 'overheating' but out of the good grip temp range of the 'A' compound. Tire pressure. yep building heat/pressure fast with AX tires and not checking pressures after every run will make basketballs outta them! even on a cool day.... |
6freak |
Oct 27 2016, 09:06 PM
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#18
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MR.C Group: Members Posts: 4,740 Joined: 19-March 08 From: Tacoma WA Member No.: 8,829 Region Association: Pacific Northwest |
I check pressure after every run and reduce back to my 'target'. By the 5th and 6th runs the car felt really sloppy and even though I was driving a better line it was slower. Not 'overheating' but out of the good grip temp range of the 'A' compound. Tire pressure. yep building heat/pressure fast with AX tires and not checking pressures after every run will make basketballs outta them! even on a cool day.... OK check and check what are they set at and whats normal ambient temp and how long are your course`s its all i can think might do what your describing those are very very good DOT AX tires and they all (Slicks)gather marbles when there hot with the Kumho 205 -50-15 tire i run 22-24 in front 24 26 in back, colder days (PNW) its more to the lower PSI.but i like my car a little on the loose side and i can feel the car going away with lower PSIs ..our course`s are very tight in the 56 second time range and i like to slide the back end around the tight turns 0 over heat just normal build up...another 914 guy here runs same tires as you (slight flared fenders) and ive heard him say up to 32 PSI WOW! I would run those probable not at that PSI but they dont fit under my car not even the 205 50 15`s too wide .....so IMO its not the tires, its YOU (IMG:style_emoticons/default/biggrin.gif) getting faster and overcome grip factor in the way your driving! dont upset the car so much..Smooth but a little bit loose in the corners is good if you can keep the ass end hanging out there a foot or so and drive through it with the pedal to the metal Smooth = fast even if your cars not going strait and you have to counter a bit...yes strait with no slide is fastest but when you can help but slide because of your speed you then must become smooth to go faster....ask me how i know (IMG:style_emoticons/default/first.gif) I love those things Play with the PSI`s.. have fun and drive the wheels off that bitch (IMG:style_emoticons/default/driving.gif) |
J P Stein |
Oct 28 2016, 10:11 AM
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#19
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Irrelevant old fart Group: Members Posts: 8,797 Joined: 30-December 02 From: Vancouver, WA Member No.: 45 Region Association: None |
My "rule of thumb" was 40-50 AX passes and the tires are either close to or totally heat cycled out. Ignore this if you like getting whupped by some one that doesn't .
Fresh rubber is the cat's ass. Just another step in the process....... |
mskala |
Oct 28 2016, 12:52 PM
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#20
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R Group: Members Posts: 1,925 Joined: 2-January 03 From: Massachusetts Member No.: 79 Region Association: None |
One of these with the 'adhesive remover' type blade makes it possible to clean
up afterward. |
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