Weird Tire wear on kumho v710s. I just got a set that were slightly used(heat cycled apparently) pleanty of life still in them though.

I went to an auto-x today. Got 5 runs on grippy airport tarmac, the weather was hot and the tarmac was 112 degrees(measured with someones pyrometer). I ran 36 front, 40 rear in a mini cooper s with no options aside from lsd. The fronts look fine, pretty much the same as before, the rears look like the tires melted(runny candle wax style) and alot of the melt solidified on the tire. Does this mean I'm running too much pressure in the rear or too little? Also what is this called?

 

It's called "OPR" or Other People's Rubber. It is your warm rear tires collecting rubber left from other people, and since the rear tires don't do much work, it doesn't get worn off. I've had some pretty nasty collections on some of my rear tires.

Jake

 

It is mostly your own rubber, transfered from the front to the rear.

 

hmm, I would have never thought that.

My first two runs on these tires were awesome, after that I started losing a little grip, that or pushing it harder each lap, i'm not sure which. My lap times went something like this

56.7, 53.5, 52.5, 52.7, 52.3

Should I be spraying down the tires after each lap. I put my hand on them and they were pretty hot. How much does spraying help?

 

Well, spraying for me has helped A LOT, even when I've been using Azenis. I use water pretty liberally on both intercooler and tires, ever since my Azenis got way too greasy and lost grip and tire life. I usually empty a sprayer pretty quickly at one event. I'm actually going to bring a second sprayer due to the extreme heat that we've been dealing with. 100+ on average, and I can't even imagine how hot the surface is.

My 710's are coming in this week and I have an event this Saturday. I will be spraying these bad boys down after every run.

 

You are picking up "marbles" which is normal. You have to clean them off by weaving back and forth or with a scraper in the pits.
I have a scrubbed set for V710 205/50-15 for sale in the marketplace if interested.

 

Your front tire pressures seem a bit low to me, 40-44 is a better range. The 710's should be warm but not hot. Water does them tons of good.

Off topic, who has tried the A06's and how are the holding up?

 

We got a ton of rubber on the rears at Milwaukee...almost as much as we did at Topeka!

Per