M3EvoBR

I usually see around 20 days + out of the PFC discs, but I have seen them cracking (all the way) with just a few days, but not common.

Vonschmidt

Great photos showing what's normal, so many people think any cracks at all is a death sentence. We have had our current set on for 36 cycles with just the start of cracking.

willk47

Most of the cracks looked like that but 2 others were much more significant.

willk47

When you say cycles do you mean days or times out on the track?

KOAN

Can someone please show me when a rotor's cracks are big enough to call it a day? I probably replace mine too soon, but I tend to err on the safe side. Mine look like the ones pictured above, after about 35-40 half hour sessions. I was about to change them this Spring as part of my "refresh".
I've run PFC rotors with 06/01, and it works well and is balanced, but like Dell, prefer 01/01. Much lighter touch needed to modulate, but gives meaning to "hand of God"...nice to have it when you want it. Much harder on rotors too.
I go back and forth.

gator9_911

Those pics look just like my demans. Running pfc 08s all around. When does normal cracking become "too much " cracking ? Is it the length?
Have about 16 days and a lot of sessions on mine. Looking for the easy tell tale sign. Thanks!

himself

The cracks below are bad. [Images from various Rennlist posts]. Most rotors will take a lot of abuse before they get this bad.

-td

Gofishracing

First picture Giro Disc?

willk47

First pic is very similar to mine in terms of width. Length is a little longer.

Fritz Flynn

Rule of thumb is when the crack goes all the way to the edge or you can see it looking at the top side of the rotor. Once it's made it's way out to the edge you could be just a heat cycle or two from the rotor completely splitting in half so no reason to risk running it any longer.

willk47

Does width matter? Like if you can see any gap between the sides of the crack.

Vonschmidt

Times on track like heat cycles on tires

mkk62

Dell
Yeah. Preference. Was having a little difficulty managing turn in and trail braking with the old setup of pagids blacks back yellows front would cause a lil turn in oversteer that went away with yellows all around. Wouldn't notice at 80% but when haulin would. Love the pfcs. Will have to try 01's but fine right now. Driving style big factor IMHO.
It's amazing what a pro setup can do as I drove 2 6-3's recently that were just as fast but felt like I was in a high speed boat with 6 ft waves. Mine like the flats in islamarada no wind.

LVDell

Interesting. You should have more oversteer under trailbraking with the less friction compound in rear.

Yeah, the PFC's are amazing. I have since gone to 08's F&R.

KOAN

Dell,
How would you characterize the 08's? More or less bite than 06's?