Flat spotted tires?
#1
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Flat spotted tires?
I was practicing some hard stops from 110-30 today and on one of the runs I really locked the fronts up enough to flat spot them both. Besides ordering a proportioning valve to get some rear bias and more practice, what do I do? I've been told to put them on the back and do a big smokey burnout, but I don't know if that will fix them? Toss them in the trash because they're junk? Leave them on the front until I get a feel for the new brakes? Have them shaved if I can find someone to do it? Any ideas?
#2
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I've heard doing burnouts with them on the back only makes them worse. The tire rotates until the flat spot, then hops when it hits the flat spot, making it worse. At least that's how I understood it. If you can't live with the vibration, I'd say they're junk. If they have good tread and you know of a place that'll shave, that's worth a shot. What tires are they?
#5
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They are RS2s. You've really got me curious about the burnout thing now. I'll give it a try just to find out for sure.
You don't want to know. It was fun though, all fourth gear pulls to redline so I'm guessing it was around 110.
I guess I'll keep them on until I feel comfortable braking with this setup so I don't destroy another pair. These brakes/pads definitely grab so much harder than the stock brakes. Time to order a proportioning valve to let the backs start helping out, they don't even feel like there doing anything.
You don't want to know. It was fun though, all fourth gear pulls to redline so I'm guessing it was around 110.
I guess I'll keep them on until I feel comfortable braking with this setup so I don't destroy another pair. These brakes/pads definitely grab so much harder than the stock brakes. Time to order a proportioning valve to let the backs start helping out, they don't even feel like there doing anything.
#9
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Good to know, didn't really think about that. I'm sure this won't be the last set of tires I destroy.
#10
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i flatspotted some old azenis 215s on the track and they eventually wore round after a long time. only problem is they kept locking up on the same flat spot every time I tried to threshold brake..... so if you're braking hard a lot, dump them.
#11
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I mildly flatspotted my RS2s at an autox. Cold day, cold tires, cold brakes. They weren't so bad as to be trash, just annoying. I think I've done 4 track days on them since and they have maybe gotten a tiny bit better, but not much, still annoying. It will probably help if you swap the flatspotted ones to the rear and run the good ones up front.
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Like Matt said, the biggest problem is that once you flatspot them, they will continue to lock on the same spot and it will just get worse.
Move them to the back, and if you can't feel the flatspot from vibration enough to bug you, forget about it. As long as you haven't really trashed them, like burning through half the remaining tread or into the cords or something, they should wear round again eventually. Moving them to the back will do two things - first, it will make you much less likely to lock them again, and two, it will lessen any vibration they do cause.
If you keep locking them up, or you can feel a vibration, dump them. When flatspots are REALLY bad you can actually feel them as a high-frequency shake in the wheel that gets worse during hard cornering.
Glad you like the brakes, Jason. The prop valve will make a big difference as well - you should be able to really dial them in nicely with the Sport rears.
Move them to the back, and if you can't feel the flatspot from vibration enough to bug you, forget about it. As long as you haven't really trashed them, like burning through half the remaining tread or into the cords or something, they should wear round again eventually. Moving them to the back will do two things - first, it will make you much less likely to lock them again, and two, it will lessen any vibration they do cause.
If you keep locking them up, or you can feel a vibration, dump them. When flatspots are REALLY bad you can actually feel them as a high-frequency shake in the wheel that gets worse during hard cornering.
Glad you like the brakes, Jason. The prop valve will make a big difference as well - you should be able to really dial them in nicely with the Sport rears.
#14
What I want to know is....... what brakes did you put on?
I had an old set of r-comps that was was driving around on the street with because I was trying to wear them down (had bought a new set and couldn't let myself take the old ones off until they were showing cords....I don't waste rubber). So I got really good at 30mph rolling burnouts. My dumbass did it and looked back and saw all kinda cool marks and smoke....and as soon as I let off the brakes the car started vibrating like hell. Turns out I locked up both fronts and was pushing them at ~40mph or so for about 75ft Wasn't down to the cords or anything, and they eventually rouded up....only for me to finish them off with two massive 2nd gear power brakes
I had an old set of r-comps that was was driving around on the street with because I was trying to wear them down (had bought a new set and couldn't let myself take the old ones off until they were showing cords....I don't waste rubber). So I got really good at 30mph rolling burnouts. My dumbass did it and looked back and saw all kinda cool marks and smoke....and as soon as I let off the brakes the car started vibrating like hell. Turns out I locked up both fronts and was pushing them at ~40mph or so for about 75ft Wasn't down to the cords or anything, and they eventually rouded up....only for me to finish them off with two massive 2nd gear power brakes
#15
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I put the Trackspeed Engineering setup on the car with XP10/XP8 pads. Every car I've owned for the past decade has had abs besides this one. The stock brakes/pads/lines have always felt ok to me for what I did with the car, but it now has a completely different pedal feel. It's as if I'm learning to brake all over again. I think I'll practice in the rain a bit more.
There's one thing I do know for sure, every part of this car is more capable than the driver.
There's one thing I do know for sure, every part of this car is more capable than the driver.