[Neptune7]

Lol, was wondering when this would turn into another CCB vs steel thread. Held out long enough.

FWIW - none of these discussions matter other than real world testing with real cars. And results seem mixed. Steels are clearly good enough. e.g. Steels on M5 stopping as well as CCBs on M8C in Carwow video.

I was hoping to try CCBs in the future for brake dust/curb appeal, but got worried when this thread appeared. Hopefully, it's a one-off.

[Archimedes65]

Originally Posted by TrevorM3

most people don't even track with CCB because of replacement cost.

I'm well aware of that, but those who do track Porsche PCCBs see way more miles than 15,000 before they're dead.

[Archimedes65]

Originally Posted by Can-am

I'm not saying that the "regular steel brakes" are bad.
I test drove one without CCB's, but man there's a huge difference!

I notice the difference much more on my Porsches than the M5. I test drove an M5C with CCBs and didn't think it was that big of a difference. I've really been surprised by how good the standard brakes on the M5 are. On a Porsche, I wouldn't buy a car without PCCBs unless it was gonna be a full time track car. They're just so much better.

[TrevorM3]

the steels are perfectly fine for DD, or even spirited DD.


The main reason i got CCB, was for no brake dust. my father did the same for his f90.

[KBM5]

Originally Posted by TheRealBob

The wear indicator on the rotor clearly indicates heavy usage. It would very much surprise me to see BMW replace this for free. In fact, if the other rotors are equally as worn, they will need replacement as well.

Technical information on CCB's - https://documentcloud.adobe.com/link...2b10&pageNum=1

I looked through the PDF and it clearly shows the pictures I posted of my breaks, the the wear circles are very visible, and the disks in a good shape.

[KBM5]

Originally Posted by TrevorM3

wow, didn't even notice the wear indicator was worn on OP's pic..


looks like someone had more than "one' trackday..

I genuinely had a 10 Minute lapping session with my car about a year and a half ago. Nothing more, nothing less. I do drive my car how it is meant to be driven on highways, however nothing to cause such a chip in the rotor.

[KBM5]

Originally Posted by Demon Barber

Here's a pic of one of my front rotors with 30k kilometers and 0 track days. Maybe the OP had a particularly brutal day at the track to explain the wear sensors, but as far as the missing chunk goes, that shouldn't happen with part of the wear sensors intact. I say premature failure.

I agree with what you say. Definitely a premature failure. However, I've only been to a 10 minute lapping session. I do drive fast on highways, but again the car is mean to be driven that way. I'm also very cautions with my CCBs and always allow them to cool off for a good 5 minutes at a steady speed before stopping completely.

I consider this to be a premature failure especially at 23K Kms.

[KBM5]

Guys,

I appreciate all the feedback and the knowledge. All your answers are very valuable for me and gives more tools to tackle the situation properly. This is what is happening as of today:

I was in the BMW dealership and showed them what the issue was. They said is does look like the disk failed prematurely. A CCB is not supposed to do that even if you wear it excessively. My wear indicators are still very visible. (The more you see the circles the more life you have on the disks **Visual check**), the more the circles are faded the sooner you have to change your disks. Do note that for a definitive answers you need to weigh your disks.

That being said, the dealership is going to try to pass them under the warranty as the mastertech at my dealership truly dosen't believe a CCB should fail this way even after heavy abuse and even less at 23 kms. I'm waiting to see what is going to happen. I have been told though that if I were to pay for it, it would run me about 8000 CAD for a single rotor.

End of the day, I should be getting a definitive answer from BMW in 24 to 48 hours on wether they are covering them on the warranty or not, or if they are changing only one disk or both and if that includes the pads or not.

Hopefully, I'll have the better case scenario of having everything covered under the warranty. I will definitely let you guys know the outcome of the situation.


As for the guys debating on my "real" track usage. I confirm again. My car has been on a single lapping sessions for 10 minutes. I loose nothing saying I tracked my car more or less, I'm on these forums to learn and share my experience and not hide anything.

Thank you all for your input!

[euro*]

Originally Posted by KBM5

I looked through the PDF and it clearly shows the pictures I posted of my breaks, the the wear circles are very visible, and the disks in a good shape.

I truly hope everything works out for you, and you get your rotors replaced under warranty.

About PDF file, you are looking at it wrong. First there is a circle that is barely visible, which is just the outline and that is only on rotors that are still matte finish (brand new never driven) . Then once the rotor has been used the circles go away and not visible at all. Once you start wearing out the rotors, the circle starts to reappear more and more material missing in the circle, indicating wear, and that is the stage of your rotors.

[AllForTheCash]

Originally Posted by euro*

About PDF file, you are looking at it wrong. First there is a circle that is barely visible, which is just the outline and that is only on rotors that are still matte finish (brand new never driven) . Then once the rotor has been used the circles go away and not visible at all. Once you start wearing out the rotors, the circle starts to reappear more and more material missing in the circle, indicating wear, and that is the stage of your rotors.

I thought he was looking at it the correct way as the pdf new rotor has the clear round circle. But his dealer confirmed a defect and not wear. His dealer also confirmed this...more circle visible is good (less wear) as he has

[TrevorM3]

Originally Posted by euro*

I truly hope everything works out for you, and you get your rotors replaced under warranty.

About PDF file, you are looking at it wrong. First there is a circle that is barely visible, which is just the outline and that is only on rotors that are still matte finish (brand new never driven) . Then once the rotor has been used the circles go away and not visible at all. Once you start wearing out the rotors, the circle starts to reappear more and more material missing in the circle, indicating wear, and that is the stage of your rotors.

wait, now i'm confused.

how does that work? it would make more sense once the circle starts wearing away, the rotor is used.. no?

[euro*]

Originally Posted by TrevorM3

wait, now i'm confused.

how does that work? it would make more sense once the circle starts wearing away, the rotor is used.. no?

Lol, did you guys read the pdf?? Page 8, shows and brand new rotor, still matte finish, that's where you can see the outline of wear indicator that will disappear once you start using the rotors. Page 9 showing used rotor, all shiny, but circle is gone and just little specs starting to reappear. Page 10 showing way more specs are missing and circle fully reappeared. Same like OP's rotors condition.


The whole point of this wear indicator is to be hidden once the user started using the car, and to reappear after the rotor has been used.

[Demon Barber]

Originally Posted by euro*

Lol, did you guys read the pdf?? Page 8, shows and brand new rotor, still matte finish, that's where you can see the outline of wear indicator that will disappear once you start using the rotors. Page 9 showing used rotor, all shiny, but circle is gone and just little specs starting to reappear. Page 10 showing way more specs are missing and circle fully reappeared. Same like OP's rotors condition.


The whole point of this wear indicator is to be hidden once the user started using the car, and to reappear after the rotor has been used.

Yeah we read it, but I'm not convinced his are past the disappeance phase and into reappearance/etching beneath the friction surface phase, but look more like partially into the initial disappearance phase of the wear indicator. Hard to tell for sure without seeing it in person, but it's hard to conceive how his CCBs could be that worn at that mileage, and I tend to believe him regarding his track time.

[Demon Barber]

Originally Posted by KBM5

Guys,

I appreciate all the feedback and the knowledge. All your answers are very valuable for me and gives more tools to tackle the situation properly. This is what is happening as of today:

I was in the BMW dealership and showed them what the issue was. They said is does look like the disk failed prematurely. A CCB is not supposed to do that even if you wear it excessively. My wear indicators are still very visible. (The more you see the circles the more life you have on the disks **Visual check**), the more the circles are faded the sooner you have to change your disks. Do note that for a definitive answers you need to weigh your disks.

That being said, the dealership is going to try to pass them under the warranty as the mastertech at my dealership truly dosen't believe a CCB should fail this way even after heavy abuse and even less at 23 kms. I'm waiting to see what is going to happen. I have been told though that if I were to pay for it, it would run me about 8000 CAD for a single rotor.

End of the day, I should be getting a definitive answer from BMW in 24 to 48 hours on wether they are covering them on the warranty or not, or if they are changing only one disk or both and if that includes the pads or not.

Hopefully, I'll have the better case scenario of having everything covered under the warranty. I will definitely let you guys know the outcome of the situation.


As for the guys debating on my "real" track usage. I confirm again. My car has been on a single lapping sessions for 10 minutes. I loose nothing saying I tracked my car more or less, I'm on these forums to learn and share my experience and not hide anything.

Thank you all for your input!

I hope all goes well and they replace at least the one rotor under warranty. Please do provide all the details and paperwork to us that you can, as this case and associated documentation could set a useful precedent for future dealership/BMWNA handling of CCB failure.

[KBM5]

Originally Posted by Demon Barber

I hope all goes well and they replace at least the one rotor under warranty. Please do provide all the details and paperwork to us that you can, as this case and associated documentation could set a useful precedent for future dealership/BMWNA handling of CCB failure.

Very much appreciate your wishes. I should know very soon. And yes as soon as this story is over and with gods help have my rotors replaced and everything back to normal, I'll definitely paste all the documentation I can to help out other F90 M5s that may suffer from the same issue and have dealerships decline warrantying breaks.

Keep you guys posted!

[F90M5C]

8k for a single rotor ?! wow my brake dust doesn't bother me anymore tbh
so happy that i skipped that option as it would have been extremely expensive with my driving style lol.

OP i really hope BMW will cover them on the warranty .

[Alberta]

One single rotor doesn't cost 8k ...

[TheRealBob]

The second photo in the original post documents substantial wear as evidenced by the wear indicator. I'm not sure why the controversy here? So, the obvious question is ...does the wear indicator on the opposing rotor paint the same picture? If it does, then the brakes have been subjected to conditions contrary to those described by the OP.

I have no reason to disbelieve what he is telling us, so it remains a bit of a mystery. Is he the original owner, or has anybody other than he ever driven the car?

For those of you with carbon brakes (I don't have them); take a look, and see if you have missing material from your wear indicators. I would bet that any cars without track time, don't look like those of the OP.

I appreciate KBM5 following up with us and wish him well.

[Alberta]

I'll try to post a good pic tonight.

Mine has 32k km and never been on track.

[Alberta]

Pics from today

[Alberta]

.

[MNoob]

Originally Posted by Can-am

.

Based on all the surface cracks and holes, I'd say you shouldn't drive on those.