I have a set of Kumho 712's on my car, with about 2500 miles on them. I have been to 2 track days and I just looked at the fronts closely this weekwend and noticed that they have about 1/8 to 1/4 inch chunks in them, most of them are about 2 inches in from the inside of the the tire. I did have an alignment done before I mounted them and everything was within factory spec, I also have GC/Koni yellow shock strut combo. Has anyone else had this problem ?
And they are 215/45 16 on Kosei K1

 

The tire size is 205/45 16.

 

what air pressure are you using. was it very hot at the track, sounds like you need to increase your air pressure.

 

I usually run 42f 40r, it was not vey hot at the track maybe in the 60's both times.

 

It is cause they are new. THe tread height can't handle the heat and pavement surfaces. My SP9000's have about 3000 miles on them and do the same thing at Auto-X and track. Wear them out a little more.