I do track days with my GTR Pro and capture tire, brake-pad and carbon-ceramic (CCB) rotor wear data after each track day. I have a Carboteq tool so I can get proper/accurate CCB rotor wear data.

Since I've accumulated enough initial CCB rotor wear data, I created a spreadsheet to help me understand the current (and future) data. I've attached the current data as a graphic and as a PDF. In addition to the track days that are on the measurement spreadsheet, there were 2 Mission track days run prior to obtaining my Carboteq tool (so 17 track days, thus far).

Track Notes
---
The 3 track characteristics are as follows:

- Mission : a short twisty track with 3 significant braking zones and lap times that allow little time for brakes to cool (it's known for "cooking" brakes) -- this is my "home" track on which I'm the most familiar/aggressive

- VIMC : a short very twisty track with average+ brake-wear implications -- it's very technical and I'm still coming up to speed on it

- Area 27 : a "proper" track at which I'm still very much a learner so probably average- brake wear (for me)

The car has the excellent TiKT brake-cooling ducts on front and rear wheels. This is important as it's heat that "wears" CCB rotors.

Carboteq Measurement Variances
---
I've not seen any Mercedes-specific instructions on using the Carboteq tool so I use it as specified by the Carboteq user manual and their video:
... well, almost ...

Since I measure the rotors after each track day, I often take the measurements with the rims/wheels mounted (light-weight forged alloy 10-spoke rims). It's clear that taking a Carboteq reading with the wheels/rims mounted on the car yields lower reading values than with the wheels off, falsely indicating a more worn rotor (by around 10%). Recognizing this allows the "wheels on" data to remain useful but, near the end-of-life for the rotors, it will be important to do measurements with the wheels off.

In fact, taking a Carboteq reading with the metal backing plate (from the TiKT
brake-cooling duct) behind the Carboteq tool produces a reading that's about
2.5 lower, when the wheels are off. That is, I get significantly different readings depending upon the rotor's rotational angle and what's behind the rotor, at that position. As such, I try to take the readings at approximately the same rotational position. Again, it's important to take any end-of-life measurements with the rotor detached. Fortunately (from a safety POV), the wheels and backing-plate interference produces a more pessimistic (thus safer) wear-level indication.

I did some simple tests to see how some "behind the rotor" materials might alter the Carboteq readings. I did the tests using the tool's calibration plate and the following material plates where the materials were added under the calibration plate:
3.0 mm plastic
1.8 mm steel plate (strong magnet adherence)
1.5 mm thick aluminum
0.5 mm thin aluminum
3/4 in painted plywood bench-top

reading | Condition
--------+-----------------------------------------------------------------------
59.7 | calibration plate then plastic then bench-top
59.5 | calibration plate then bench-top
59.4 | ##### calibration plate, only #####
59.3 | calibration plate then plastic then thin aluminum
59.2 | calibration plate then plastic then steel
59.1 | calibration plate then plastic
59.0 | calibration plate then steel
58.9 | calibration plate then thin aluminum
58.8 | calibration plate then plastic then thick aluminum
58.5 | calibration plate then thick aluminum

Wood raises the readings (moisture content?) and plastic and metal materials lower the readings, consistent with what I see with measurements at different rotor rotational positions, on the car -- not to say that the GTR has any wooden hub/rotor/brake/wheel parts ... at least not that I know of. $;-)

Results
---
As I've written in other posts, I've only found anecdotal evidence about CCB rotor wear with track use, but there are implications that CCB rotors (with good brake cooling) may last 40+ track days.

In the video
(at 5:25)
Opus implies that they got ~10K km track use from Black Series CCB rotors.

If you averaged 150 kph on your tracks, that's over 65 hours of track running,
at speed ... or 195 20-min sessions or, at 5 sessions per track day, that's
39 track days. So it seems like CCB rotors might actually be good for 40+
track days.

My measurements seem to be moving towards the same conclusion, assuming that the wear doesn't go non-linear at some point in the future.

I do see some anomalous readings in my data. Aside from the possibility of human recording/transcription errors, there's also the issue of the rotational position. Since building this spreadsheet and doing the material tests has helped me understand things more, I'll try to be even more precise with future measurements.

I've also found that it's important to apply the same pressure to the tool so it sits equally snugly against the surface of the rotor. Finally, there's the fact that any digital tool is (by definition) only accurate to +/- 1/2 of it's least significant digit, so there's always that variance.

Still, it's nice to finally see an encouraging collection of actual data (well, at least if you're a geek, like me). #;-)

 

Nice information and very interesting tracking wear!

Have you ever had any noise after a track day from your brakes? I did 2 track days with my CCB and now when I brake I can hear a slight grinding/scrapping noise, only very feint. Pads are all 8-99mm remaining. I seem to be wearing through approx 1mm of front pad per track day, using cooling ducts.

I've also spotted that the rear discs have a slight cloudyness to the surface and the fronts have what looks like pad deposit, either slight indent or raise (can feel it with my fingernail) in a circle all the way round both discs.

 

Yes, I can hear what's likely the same noise you describe during street driving. I did "bed in"/burnish my rotors but found that a Mission track day seems to remove (burn off?) the pad burnishing on the rotors so, after 2 bed-ins, I gave up and just accept it. For me, when the brakes are cold or track-warmed, they don't squeal. However, after only 1 aggressive braking event (e.g., to quickly scrub off speed after some number of seconds of WOT "test"), they'll squeal until completely cooled (thus telling everyone that "grandpa's been bad!").

I also once had a small rock get lodged between the rotor and pad, when at the track. Sounded pretty horrendous but a little "backup with braking" cured the situation (whew).

An average of about 1 MM of pad wear per track day (Pagid pads) is also what I'm seeing. That's the least amount of pad wear I've had with either the C43 or (especially) the C63 S. I was quite pleased with that aspect. I don't know whether it has anything to do with the CCB rotor material or whether it's just due to the pad hardness, but I'll take it.

 

Good to know regarding the slight noise.

I thought it might have been a rock or debris that's caused the marking all the way around the disc but its on both discs which would be extremely odd! Using RSC1 pads.

 

What's the cost of the Carboteq tool? I might need to get one.

 

Amazing data, thank you for doing this! I feel much better about tracking on the CCBs now

 

I may be wrong but I’m fairly certain it is several thousand dollars.

 

I'm in Canada and purchased mine in Q1 of 2022. It cost me a little ove $9,300 CAD (!), delivered (and it took about a month of badgering the company to get information on how to buy it, believe it or not).

 

After doing another track day, I've updated the spreadsheet and data to incorporate an additional set of measurements both with wheels off and wheels on and to include the following comments:

• when taking readings with the Carboteq tool, it's important to ensure that the tool is consistently held tightly against the circumference edge of the rotor and flat against the surface of the rotor — even tiny gaps will cause significantly altered and inconsistent readings

• readings taken with the Carboteq tool when the wheels are on the car will result in different values than when the wheels are off the car — with the lightweight forged alloy wheels on my AMG GTR Pro, the "wheels on" readings show 10+% more "rotor wear" than the "wheels off" values (it is expected that different metal wheel materials and styles will each affect readings differently, but will likely always show more wear with "wheels on" measurements)

• readings taken with the Carboteq tool in a position where there is a metal backing plate behind the rotor will result in different values than readings taken in a position without a metal backing plate — on my AMG GTR Pro, the rear-rotor readings taken in a position where the steel backing plate exists show 12+% more "rotor wear" than the readings taken in a position where the steel backing plate does not exist

• above, the readings from 2025-08-01 and later were taken with an understanding of the comments above, so — 1. readings were taken with the measuring point at closely the same rotational position to help ensure consistency — 2. multiple measurements were taken to ensure 3 readings agree to help ensure accuracy — 3. when wheels were removed (e.g., to replace tires or do left/right rotation to even out tread wear), both "wheels off" and "wheels on" measurements were taken/recorded

• the GTR Pro from which these readings were taken had 2 Mission track days prior to acquiring the Carboteq tool and taking the initial measurements — so, as of 2025-08-01 with a total of 17 track days (typically 1-1.5 hours of track running), the rotors appear to be wearing linearly, have had about 30% of their life used (so 70% remaining) and (assuming continued linear wear) should last more than 50 track days

At this point, I feel that I have a pretty good understanding of the track-use CCB rotor-wear situation for my car. I'll keep posting updates as I get more data.

 

I was experiencing a troublesome noise issue as well. Did numerous aggressive burnishing and gave up for a while. It was driving me nuts so I took a gamble and ordered a different pad formulation and NO MORE NOISE. You can also try to switch the pad positions to see if it can reduce the noise. Switch inboard pads to outboard and so on.

 

@user33 INVALUABLE DATA

Greatly appreciate you taking the time to carefully measure and compile all of this data - THANK YOU

@mods: This Thread belongs in the parthenon of Sticky, please

 

Thanks for the info. My first set of front pads was the TiKT/Pagid formulation and they did not have the "scraping" noise. Unfortunately, TiKT was unable to supply those same pads when I needed to replace the first set so I'm now on OEM pads.

I not only have the "scraping" noise (which I really don't care about) but the front brakes are also somewhat more "grabby." When being aggressive in serious braking zones, I find it about impossible to prevent some amount of anti-lock activity before I start to trail off (well, I could brake sooner and not fully, but where's the fun in that?!). Less than ideal. Yeah, life is soooo tough ... then you die -- yeah. #;-))

 

Makes me wonder why they don't add the harmonic counterweights like for the regular iron brake systems. Are you running lubricants for the Calipers? I tried that with my first set of pads and they didn't do anything to mitigate the noise. When I switched to the Pagid pads, I installed it cleaned and dry.

Also you should consider add temperature measurements to your data set. Some of these stickers from AP Racing or Brembo are also a good tool.

 

I'm on Pagid RSC1s, the only time I had noise was after the very first track day, the brakes would make "ship horn" sounds on full lock, went away after the 2nd track day

 

This is extremely helpful data, thank you OP for sharing!

 

I've always used a very thin film of one of the WIS recommended greases for the back of the pad. I also doubt it makes any difference on the GTR's brakes.

I've always used the temp pads, 1 on rear calipers and 2 (1 top back-side, 1 bottom front-side) on front calipers. Currently sitting at:
Driver Front Bottom: between 210 and 232 deg C
Passenger Front Bottom: between 210 and 232 deg C
Driver Front Top: between 188 and 210 deg C
Passenger Front Top:between 188 and 210 deg C
Driver Rear: between 188 and 210 deg C
Passenger Rear: between 166 and 188 deg C

I've been using Motul 660 fluid which is spec'd for a dry boiling point of 325 deg C and a wet boiling point of 204 deg C (though they don't specify the moisture content) and have never had any brake fade, which is consistent with the measured temps. I have one of the little 2-prong multi-LED battery-operated fluid-moisture indicator-tools and have never had any moisture percentage show when bleeding my brake fluid. I see that I can now get Endless fluid via Amazon so I'll likely use them next time (Castrol supply is iffy via Amazon in Canada).

 

Wear is proceeding linearly and as expected, based upon the data thus far.

 

How do your discs visually look? Comparing mine to PCCB I seem to have a lot of pad deposit, or some sort of rotational marking around the discs, whereas PCCB always look extremely clean and mirror like finish even after using on track.

 

Mine look like this ... very "cleaned off." Twice I went through the process of (taping off the TiKT brake-cooling duct intakes and) doing a "brake bed-in," only to have the pad-deposits wiped clean at the next track day ... so I stopped doing that (pun intended). #;-))

 

Good info. Thanks

 

Mine look quite different! This is with RSC1 pads.

 

Yeah, yours have some pad deposits indicating that some brake "bed-in" has taken effect ... and remained. That's what we'd all like but, in my case, it gets wiped (burned?) off when I run a track day.

With the pad deposits on the rotors, you should have smoother-operating brakes that are less likely to squeal. Be happy. #;-))

 

Yeah there’s definitely no squeal but slight rumble at low speeds as you can hear the pads on the rotors.

I was on track this week and it was about 50F so I wasn’t pushing it like I do with the warmer weather.