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wepsbee
09-08-2009, 09:35 AM
I am running Toyo R888's and have found what is to me an unusual wear pattern. The 888's as you know have chevron like grooves. I have on the front tires a pattern where the inside groove edges are sharp and very worn. The outside grooves however are not as worn and the edges are kinda rolled with excess rubber built up along the entire groove. The outside edge of the tire also has turned slightly blue. Is this a camber issue?? I have adjusted the camber down slightly as suggested by Toyo and the Miata crew who use these tires. I also adjusted the tire pressure down significantly and the temps were even across the tire after the last race.

Andy Bettencourt
09-08-2009, 01:28 PM
The camber and pressure ideas seem solid. The blue you describle sounds like UV damage from exposure to the sun.

wepsbee
09-08-2009, 02:25 PM
The camber and pressure ideas seem solid. The blue you describle sounds like UV damage from exposure to the sun.
Will the UV damage render the tire unsafe or unuseable?

europeanspec
09-08-2009, 02:36 PM
I am running Toyo R888's and have found what is to me an unusual wear pattern. The 888's as you know have chevron like grooves. I have on the front tires a pattern where the inside groove edges are sharp and very worn. The outside grooves however are not as worn and the edges are kinda rolled with excess rubber built up along the entire groove. The outside edge of the tire also has turned slightly blue. Is this a camber issue?? I have adjusted the camber down slightly as suggested by Toyo and the Miata crew who use these tires. I also adjusted the tire pressure down significantly and the temps were even across the tire after the last race.
The blue may be from rubbing, as well.

rsx858
09-08-2009, 03:06 PM
The "Bluing" on the edges is very common for me running hoosiers. I have had old tires turn blue and even tires with one weekend on them turn blue... could certainly be sun damage, but i have not noticed a substantial drop in performance caused by the bluing specifically.

joeg
09-08-2009, 04:11 PM
"Blueing" is overheating--not rubbing or UV exposure.

Burnt tire rubber "blues".

Can be camber, over aggressive driving, etc.

wepsbee
09-08-2009, 05:18 PM
"Blueing" is overheating--not rubbing or UV exposure.

Burnt tire rubber "blues".

Can be camber, over aggressive driving, etc.

Camber I understand, as a fairly new driver you are gonna have to explain"over aggressive driving". I have been on the track and have been "nudged" by aggressive driving which I have been under the impression is required to excel at this sport.

Streetwise guy
09-08-2009, 10:38 PM
I have found, on my front wheel drive 2650 lb Neon, that the edges of all the grooves tend to feather quite dramatically. I have also found that they "blue up" quite easily, particularly on the edge of tread. My tire temps, taken by me after a cooldown lap, climbing out of the car, finding the pyrometer, etc usually show up around 160-170*F My guess is Toyo is accurate in their high limit being around 200- I have had them go off when pushing very hard for more than 10 minutes. I have also found that they really don't drop off with repeated heat cycles, even if they are blue on the edge. I "think" they are fastest for 3 laps from sticker, them slow off slightly and are then consistent to cord.

I am having a bit of a time figuring how you are wearing the inside half more, but not feathering that side.

Also, I have found that I need at least as much camber and pressure as the ra1, but mostly to keep from cording the edge of the tread where it rolls over to the sidewall. They may be faster with less, but I'm not willing to buy that many tires, and the temps are actually quite even all across the front of the car.

Ed Funk
09-09-2009, 07:36 AM
What's your total toe out?

wepsbee
09-09-2009, 07:46 AM
What's your total toe out?
It is whatever the stock adjustment is supposed to be. I do not know but I will find out.

joeg
09-09-2009, 08:07 AM
Dan--Forgeting tires for a bit, you need to experiment with toe. Try 3/32nds" total toe-out in the front; 1/16th " total toe-in on the rear as a start.

JLawton
09-09-2009, 09:00 AM
Camber I understand, as a fairly new driver you are gonna have to explain"over aggressive driving". I have been on the track and have been "nudged" by aggressive driving which I have been under the impression is required to excel at this sport.

By aggressive he means over driving the tires, which leads to over heating, which leads to the tires falling off. Usually the heavier cars need to "manage" their tires through out a race.

For example, if the car understeers and you keep driving the car harder and harder into the corner resulting in you having to turn the wheel more to get bite. This will over heat your front tires.

Hope it makes sense......

On a side note, If you're getting "nudged" by the faster cars maybe you're not getting out of the way fast enough!! he he he.............

wepsbee
09-09-2009, 11:35 AM
By aggressive he means over driving the tires, which leads to over heating, which leads to the tires falling off. Usually the heavier cars need to "manage" their tires through out a race.

For example, if the car understeers and you keep driving the car harder and harder into the corner resulting in you having to turn the wheel more to get bite. This will over heat your front tires.

Hope it makes sense......

On a side note, If you're getting "nudged" by the faster cars maybe you're not getting out of the way fast enough!! he he he.............
I do try my best not to be a rolling roadblock but both the car and driver are improving with every race so the desire to move over is not as strong as it once was!!!!

wepsbee
09-09-2009, 11:38 AM
Dan--Forgeting tires for a bit, you need to experiment with toe. Try 3/32nds" total toe-out in the front; 1/16th " total toe-in on the rear as a start.
Thanks, I will give that setup a try. Camber and pressure so far are the only things I have varied.

wepsbee
09-09-2009, 11:39 AM
By aggressive he means over driving the tires, which leads to over heating, which leads to the tires falling off. Usually the heavier cars need to "manage" their tires through out a race.

For example, if the car understeers and you keep driving the car harder and harder into the corner resulting in you having to turn the wheel more to get bite. This will over heat your front tires.

Hope it makes sense......

On a side note, If you're getting "nudged" by the faster cars maybe you're not getting out of the way fast enough!! he he he.............
BTW the last race was a milestone for me at NHMS. I was not passed or lapped and finished on the lead lap!!!!!! No nudging there!!

Carlos Gutierrez
09-09-2009, 04:35 PM
congrats ! now, throw those POS tires away, buy some Hoosiers and go run with the big dogs.
:>)

rhygin
09-10-2009, 09:39 AM
Dan... I do rememeber from our conversation at NHMS that the tires had way too much pressure. see you at the cheap date?

europeanspec
09-10-2009, 10:59 AM
It is whatever the stock adjustment is supposed to be. I do not know but I will find out.

That's the problem, for sure. You are overheating the outsides of the tires because the car is toed-in in the front and it's pushing on entry.

It's time to forget all about those factory specs. They set cars up to push from the factory because it is safer for the masses on public roads.

wepsbee
09-10-2009, 12:21 PM
Dan... I do rememeber from our conversation at NHMS that the tires had way too much pressure. see you at the cheap date?
You were the reason I ran such a great race. Your timely info was spot on and worked very well. I really appreciate the help it worked!!! I will not be at the cheap date. My next 2 races are LRP for the Runoffs and the Last Chance at WGI. Will I see you at either one of these? Thanks again.

wepsbee
09-10-2009, 12:22 PM
That's the problem, for sure. You are overheating the outsides of the tires because the car is toed-in in the front and it's pushing on entry.

It's time to forget all about those factory specs. They set cars up to push from the factory because it is safer for the masses on public roads.
It shall be changed. Thanks