Carbon ceramics and brake bedding

[+ManifoldPSI]

So how many of y'all who take delivery of a new Blackwing with carbon ceramic rotors complete the manufacturer specified bedding/break-in process?

I have just under 400mi (mostly boring smog prep miles) on my '25 5VBW PP and have yet to a) complete the burnishing steps or b) apply the brakes more than about 25% of pedal travel/braking capacity. Thus far I have mostly relied on engine braking to decelerate.

I plan to do the proper break-in procedure, but I am just wondering how many owners actually complete it, and if there are any noticeable performance differences on-track, or under street driving even, between a car that has had this performed vs one that has not. My hunch is this process is more about wear/duration than about performance.

That and if/when one would reach the point where, after a certain number of miles or amount of brake wear, actually performing a "late" burnishing procedure would have a reduced or non-existent effect (assuming it had not been done prior).

 

[rdollie]

The brake burnishing process for both setups is hard to do legally on the street. After struggling with it (found myself out at 1A on a local highway paranoid a cop was going to think I was drunk), I found the 'power lunch hour' HPDE event was perfect - just hit the track like normal and the pads will bed properly.

 

[+ManifoldPSI]

Yep, especially for those of us who live in densely populated areas. That's part of the reason I ask and am curious how many people have done it. Taking care of it on a track day seems like it could work given the right track, run group, timing etc.

 

[nordique14]

I did my CCB burnishing during the first session I had on track. That was after about 3k street miles. No real way to effectively do the burnishing in the real world without the possibility of getting in some trouble.

 

[DCV]

Brakes are cheaper than engines.

 

[fordperfaddict]

id get up early and do the burnishing process one morning. The CCBs will last longer if they are broken in properly. At least that is what my research has told me.

 

[SS_Shooter]

What is the bedding in/burnishing procedure? The typical 100 mph to 10 mph hard stops, 10 in a row or something...

FYI, I just drove the car as normal.... Brakes seem fine.

 

[jvp]

I've written long posts about this topic on here and the Corvette Forum since GM started using CCM brakes on the Corvette ZR1 during the C6 era. The burnishing process is to help season the pads, for lack of a better phrase. The seasoning is to prepare them for being VeryHot(tm). Hotter than you're likely to get them on most street driving adventures. Hotter than they'll get after a single hard stop; rather, the temps they'll see at the race track or after repeated use during aggressive street driving.

Basically, if you're never going to do either of those, you don't need to worry about the burnishing process. It won't hurt anything to burnish them, though you will more than likely start them squeaking as you come to a stop (because you've melted the anti-squeal material off the pad backs), and they WILL produce more brake dust after burnishing. Otherwise they'll be fine and you may not even notice the difference.

The challenge with the CCM pads is how they're made. The bonding material used to keep them together out-gasses when the pad gets to temperature, and that can cause a bit of an air bubble or "pad" between the rotor and the actual brake pad. This'll lead to a real uneasy feeling in the brake pedal until that pad gas has been evacuated by the rotor. Burnishing the pads starts the process of cooking off some of that bonding material, and you'll know that because the leading edge of the pads will have a white line or shading around it. But it also means the pad can fall apart a little faster. Yes, burnished pads will not last as long.

The way I approach these cars is: if I know i'm going to take it to the track, I'll burnish the pads. I'll just take the very first session I run at a slower pace, following the 6-7 lap process of a couple of laps at a moderate pace, a couple of them at near full pace, then a couple of them at moderate pace. By the time I get into the pits my brake pedal feels like shit because the pads are outgassing like mad, there's a wicked brake pad stench, and I know I've completed the task. The very next session I run at full bore knowing the pads are ready.

 

[nordique14]

Thanks for that info. I never knew that it was off-gassing that was being accomplished by the burnishing process. Makes sense as higher temps will causes trapped gas to expand and be released.

I did the same as you for burnishing. I used my first track session to complete the process and had between sessions for cool down. I also noticed that the pads create a lot of dust bug I just assumed it was the harder track braking that was the cause. The wear rate was very high for the first couple of track days but they seem to not be wearing as fast now.

 

[Atlien]

Hey jvp! I remember you from Corvette Forum. I had a C6 Z07 and burnished them on a track day. I noticed that easy highway miles wore that white layer away, however.