You were totally right. Thank you.

I think the warping is getting worse. Or it just bothers me more.

Stock rotors seem to warp easy. Mine are getting that way too. I plan to upgrade to some Raybestos rotors before my next HPDE.

No its the pads thats causing it. You cant track stock pads....

He's on Carbotech XP8's

Improper padding led to that. I did the same thing on my xp8. I was lucky that I have some xp10 to scrub the deposits off

You mean bedding?

Yes sorry auto-correct on cell phone. Yeah I had problems with the XP8 and vibration when I didn't bed them correctly the first time. Luckily I have my old XP10s in the garage, I just used the 10s to clean off the rotors and re-bed my 8s after. It's been 5000 miles since the last bedding, no vibration.

Btw, I noticed a slight hint of fade with the XP8 after some hotlaps too. The 10s are definitely better, but you are at the risk of ice mode for sure.

So are my rotors warped or improper bedding?

I resurfaced my rotors after a stock pad track day, and replaced with the XP8's. And still had a vibration. Now I've ordered new rotors. Am I making a mistake?

Your first mistake is cutting the rotor. Rotors rarely warp, the vibration you feel is from the deposits left on the rotors from the pads (too much heat or improper bedding). When you got your XP8, did you go through the bedding process that they told you to? You have to get the pads so hot that there is no pedal pressure left. Once you are done, everything should be ready to go as you really only have to bed the pad once.

Unless you are racing for money or time, buy the cheapest brand name rotor and get them cryo treated. Bed in the pads right and it should last you a while. I have gone through 4 sets of pads on my OEM rotor, no vibration or problems.