sleeperstyle

back story-

i bought a set of wheels and tires used, both in good condition. the tires were r888's, 2012 date codes, in good condition.

i did 4 total track days on them, and since 2 were rainy i did not rotate the rears, as in run them backwards to even out the wear. this would be a bad idea in the rain since the water would not run out. let's figure i had 2.5 dry track days on them..

well, after wearing a weird groove in the middle/outside of the drivers rear (mostly right hand turns as we all know) i found out about the r888's achilles heal- "the groove of death"

i will post pics up, in hopes that nobody wastes their money on these things, i am gonna try and rotate them and still run them, but i really have to watch as the groove is pretty bad..

my alignment is spot on, a smidge of toe in, barely any... -1 degree camber in the rear, 38-39 psi hot.

i read that miata guys found that they have to be run at 45 psi hot or more to eliminate the groove of death (i didn't name it that honestly, search and you will find it).. i initially thought i had too much air in them, but upon research less air makes it WORSE and wears a groove more.. i don't get it, i do know that i will need new race tires soon now, not planned in the budget but that goes with the hobby... i know i will never buy these again.

so my amateur review= they suck, don't buy them, complete waste of money to wear out a 2" section of a 11" (or so) wide tire. i am sure there will be a few who come in and say "i run them with no problems"... well i say good for you, but many have problems and i feel like people should know that before they consider buying them.

sleeperstyle

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C5ZEE06

Looks like too much air pressure ?

sleeperstyle

that is what i thought initially, until i did some research.. my fronts are fine however, and the air pressure was the same (38 to 39 hot)..

C5ZEE06

Too much pressure in rear = wheel / tire spin on exit = tire wear

72Vega

Yep, I'm of those guys who runs R888s and is very happy with them. You might want to contact Phil Phillips. He's a real racer from upstate NY who provides track side tire service to several NASA regions. He has many years of experience with lots of tire brands including Toyo. He will give you the straight scoop!

http://www.philstireservice.com/

Good luck!

sleeperstyle

Thanks for the link- I will contact ...I do agree it looks like too much pressure, but if you care to do a search for " r888 groove of death" it comes up a lot - and more than a few said they need more air pressure than people think.. This was when a miata class was forced to run them they found all of this out..

What kind of air pressure do you run, hot? If it is less than say 35 does the sidewall not feel like it gives a lot during transitions? How do the tires wear- evenly I assume since you like them?


Here is some food for thought

https://www.google.com/search?q=r888...&client=safari

sleeperstyle

With low pressure the tire will deform due to centrifugal forces. With a tiny sidewall and a long relatively wide tread, the center of the tread has nothing to support it so it bows out.

With more pressure, the inflated sidewall pulls the tread tight under tension and the tire keeps it's shape.

Or so says the Pirelli Race Engineer.



***. I quoted that from the one thread in bimmer forums.. I read that most shoot for 40psi hot- then one guy was having success with 45psi hot.. I don't think my 38-39 psi hot was too high?

NOSLO6

I've run through several sets on my C6 and haven't ever seen anything like that. I've always found them to be a good compromise tire that can get you to and from the track in dry, wet etc... I see tons of vettes & GT-Rs running them at the local track.

I've found mine work best at 37-38psi, though preferences, alignments, driving style and other factors may vary. Of note is that Toyo recommends no more than 38 psi under setup & care, but as the poster above notes there's no substitute for real racers' insights.

C2Racer

I have been using these tires since they first came out with no issues, probably 15 sets. But I have used them on a light car of 2,100#'s and cold pressures of 25 rear and 29 fronts. Never had a problem?

72Vega

with NOSLO6 Phil advised me that these tires like to run 36-38 hot.

Werks

I ran them my self and had no problem and the tires lasted probably a good 6-7 track days. There are two groups when it comes to R888's, those that believe in running really high tire pressures and those that believe in running low pressures. I belong to the low pressure group and ran hot temps of 34F/32R and was happy.

sleeperstyle

All good info. It seems I am the only one on Here with the groove problem, I am going to summit at the end of July and I honestly don't know what to do about tire pressures. If I stay at the recommended I get the abnormal wear- I may try and drop the rear pressure to 32 psi hot, and closely monitor wear.. I will also be buying a digital heat gun to monitor the surface of the tire.

skxf430

My R888's having been wearing fairly evenly but I like to run them at a lower hot temp of about 34/36. Any hotter and the tires feel a bit greasy.

mgarfias

You need a probe that goes into the rubber. The surface temps won't give you good info.

Last C5

Not enough pressure. You need 40+ hot or you get the groove in your pictures.

Werks

One thing that I forgot to mention is that I would not judge a tires performance based on the results of running one used set. You have no idea what the previous owner did with and to the tires nor how many heat cycles they have seen which is important with R comps.

AU N EGL

Pirellis are not Toyo's

Two very different tires

jvp

I like the R888s. Buy a new set from Tire Rack and spring for their heat cycling. Yeah, it's the lazy man's approach, but they actually do a good job with it.

FWIW: I'm with Werks in the "low pressure" camp. I run them around 28 or so cold.

rbl

I agree and have run probably 10 sets out on the C6 ... excellent tire with very little problem. I ran 40-42 hot pressure.

I think OP is just plain wrong.. A set of used tires that he did 4 MORE track days on that look pretty decent .. what's the complaint!