I've done two track days. My back rotors are fine, I've got a nice lip on my fronts. Two part question I think I know the answer to part 1. Any need to turn the rotors? They're not warped no degredation of brakes, just have a lip. I think the answer is no. 2. When do I know it's time to replace? If I use a caliper I'm going to get a reading on the lip not the lower section. BTW I'm running stock rotors; ceramic pads, and ATE Blue.
Thanks

 

If you spent any time at all looking for this answer, you would have found it.

1) No. 2) When they crack.

 

What he said.

 

In regards to #2

For the record ZONG9, not all of us agree with that answer...

The rotors will beging to develop many tiny little dark lines, they are check marks showing the rotors stress. I do not believe in putting myself out on track with a rotor that looks like it is about to crack. Over time you learn to see how these check marks slowly start to get more popular as well as longer and darker. I replace my rotors at least once per year, I watch the check markes and when they look bad enough for me I replace the rotors. Driving the card to a point where is starts to break, on track, to me, is just plain foolish, especially when we are talking about the replacement of a $120 part. But hey, if brake failure is somethig you are comfortable with go for it...

 

Uhm
He did say when they crack, not after they fail. You yourself said you replace them after they crack.

 

Tripple H.
can I have your used rotors...
the ones that are just starting to show the lines

 

[QUOTE=krazik,Apr 16 2008, 09:06 AM] Uhm
He did say when they crack, not after they fail.

 

[QUOTE=krazik,Apr 16 2008, 11:06 AM] Uhm
He did say when they crack, not after they fail.

 

I don't replace them as soon as they start to check, I monitor the check marks as they populate and get larger, I don't replace them as soon as they start to check. I then throw them away at a point where I feel the check marks could become full fledged cracks at the next event.

Rotors are cheap... I see no value in pushing them unti they crack.

 

In a perfect world, and the most popular case yes, but in my years I have seen rotors terminally
fail on track, jaming up into the caliper, or breaking pads that get jammed into the caliper, thus locking up a wheel, sending the car off track for a bit of farming.

Funny how after seeing things like this some have a tendency to over-maintain their parts...