dp35

Just noticed that around their outer edge, my (Yokohama A048) tires are turning blue. I've seen other types of R compound tires on other cars do this too. I've heard rumors that this means the tires are heat cycled to death, or that they were overheated, etc., but not from reliable sources.

Can anyone tell me what this means, if anything?

kary993

too hot......

JoeMag

..i've heard too hot too. maybe give yok tech support a call.

Sean F

My R6's look like that after every event. I used a set with 15 hard days on them to set my personal best time at a club race this past weekend and they had the blue ring after every event. IMHO, doesn't mean sh*t.

mooty

my tires, (all the different tires), usually only turn blue at end of their life. when i see consistent blue at edge of tread, they are usually about dead.

Larry Herman

If you don't see that blue, you're not driving hard enough.

Bryan Watts

Or perhaps you have a car setup that isn't as hard on tires as the 1300+ pound spring rates some of you Porsche guys run.

Premier Motorsp

Serious question:

Why are stiff springs hard on tires?

Larry Herman

Could be, but my car is actually fairly gentle on tires. I regularly get 8~10 track days on R6s before they're done.

Larry Herman

Hard on kidneys, yes. Hard on tires? If the alignment is right, I don't see why it would negatively affect tire life.

A930Rocket

Blue tires? Sounds like they some...

Mark in Baltimore

Tires are sad? Miles Davis fans?

FLA997

Yep...

Bryan Watts

Because the tire is doing more work and getting hotter. The tire is a "spring" as well, so as the suspension springs get stiffer, the tires become the softer part of the suspension. The tires start doing all of the work and absorbing the bumps while your springs/shocks stay relatively still. If you can't get heat into your tires, the answer is almost always to go with stiffer springs.

I'm sure the stiff setup is fast, I'm just poking a bit of fun at the insane spring rates I keep reading about on here. At some point, the springs can get so stiff that the tire and the chassis are doing more flexing than the spring/shock.

As for the blue, I've always heard it's an indicator of too much heat from friends in the race tire industry. In the end though, your best bet is just to break out the pyro and find out for yourself.

Barfly

I have had dismounted RA-1s that were exposed to a little heat and sun do this - I was in a one bedroom condo last year, so didn't have much choice but to leave them on the balcony partially covered. I still have a few of them, but feel that the grip will likely not be where they were before. In fact, a few years ago, I had some rears that were close to the cords have that bluish discoloration on them. I put them on the rears during a session thinking that I might have a little extra rear grip given that I had on 4/32" fronts, and damn near spun the car on turn 1 at Willow Springs during my first hot lap.

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Jason