badabing

I know the rule about cracks extending to the adjacent hole or running to the edge of the disc but some of these cracks are looking pretty wide/deep.

These are Sebro aftermarket on a 987.2 CS.

About 10 track days on them give or take a day or 2.

Quadcammer

If you are in doubt (and I would be also), I'd replace them. If anything, they have maybe 1 more event, but I'd just replace them now.

911racer

Yes, they are about done. You might get a bit more out of them, but it would be considered pushing your luck. They will go pretty quickly from this to having cracks running to the outer edge of the disk.

Thanks

Ed

badabing

Thanks. Not looking to risk my safety or someone else's to squeeze out a day or 2.

I was thinking they were done I just wanted to get some others opinions.

Thanks for the quick answers.

NYoutftr

Is that normal wear for sebro rotors?
10 track days does not seem like very much, did it also include street miles?

bgiere

get some Giro Disc rotors...drilled rotors are throw away items on a race/track car...Lucky you got 10 days out of them !

linzman

Slotted rotors is the way to go on a track car. Last longer, and no cleaning out the holes

badabing

Going with Giros. These have some street miles on them, mostly highway to and fro local tracks.

The oem rotors had 40K miles and also about 10 track days before they were pulled for min thickness.

Sebro may be an oem supplier but this datapoint shows the quality is not the same in the aftermarket.

Jerrygreene

ran drilled on 964 cup car. Very competitive car, we waited till the cracks went thru to the top, so you could put a finger nail in... ( make sure you look at both sides) Never an issue.. sunning padgid blacks.

mark kibort

they are fine for a DE car and if you are racing, you would have probably one more weekend on them and the cracks would start to migrate to the edges. this is the outside of the rotor,and the inners are probalby not cracking (there is much more air flow there) so, plan on changing, keep an eye on them as i have run them like this when i used drilled rotors (never again) for race duty. generally, they lasted 3-4 weekends max .. slotted is the way to go , or solid if you cant find them

morsini

Not done yet, but keep an eye on them. I would replace them if your pads are in need of changing, but otherwise run them until two cracks touch or one runs close to the outside

spg993tt

replace. - do the math. rotor cost divided by current # of days = cost per day. balance the cost of squeezing one more day against the damage to car or your body if you wreck due to failure. why fool about ? its a safety thing. never run motorsports gear to the very life.

zedcat

I have a page from a 996 era Porsche manual that gives a guideline of 7mm max crack length and no cracks to the edge. I've been using that as a guide.

mark kibort

I've been doing this a long long time ... this is just normal wear when racing a drilled rotor. its not going to be a problem.. but as Mike said, when its time to change pads, (or if you need pads now) or the next couple of weekends, change out the rotors. there is nothing to be panic'ed about here. when most of those cracks start going near the edge, its time... i would say, 1 or two more weekends and they are probably going to be time to change. keep a close eye on them.

Berringer

981? Boy do I have deal for you!
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