Do you have the weights in grams of each rotor as well as the thickness?

 

I have the weight in gigatonnes only. Let me know if that works.

 

Sorry I said rotor but I meant disc. The weight just gives me an idea of how much meat is left since mileage doesn't say anything because it's too variable with each driving style.

Can you please also provide the part numbers?

 

Weighing requires you to remove the hat off the rotor. It’s a lot of work. There are wear spots on each rotor which I’m sure you know of that help understand the state of the rotor. Those are all in tact. Either way however, I don’t want to take them apart.

 

That makes sense and would be work intensive. Thanks for letting me know.

 

Where did you learn that? I bought mine few years ago and when I weighed them, the weight was within specs what it read on the rotors and not any heavier.

 

Since your rotors are off the vehicle, thoroughly cleaning them and accurately weighing them is valid. The weight limit is imprinted on the rotor hat and is for the complete assembly, including the hat.

The best and, in my opinion only, other way to measure the CCB rotor "wear" (chemical degradation from heat) is to use the Carboteq tool. I wrote the attached paper to explain why I think this is so.

 

That pdf was very insightful. Thanks. Just posting the video linked in that pdf too:

 

learned it somewhere possibly not related the AMG. But I will weigh them and post. Reading this makes me happy because I can easily post what they are and hopefully get a buyer.

 

Alternatively (and, better yet), see if a local dealer has the Carboteq tool and get them measured.

Audi specifies that their dealers must use it for evaluating CCBs, but I don't know whether they conform. The more recent (5+ years, at least) German cars are using the (Brembo, I think) marked CCB rotors that can be evaluated using the (very expensive) Carboteq tool.

For reference, I've done 16 track days with my GTR Pro, nearly all of them on short tracks that are very hard on brakes because there are so many braking zones without long-run sections to cool. I take Carboteq readings after each track day and none of the readings are down to half-way between the upper/lower numbers marked for each of the 3 reading points on the rotors.

A couple of years ago, my extensive searching found anecdotal evidence that CCBs may last 40-50 track days, but no-one had published any real data. If the wear-number degradation is linear, then my measurements would seem to indicate that that is likely the case. If the wear (heat-caused chemical degradation) goes exponential, at some point, then that won't be the case. Time will tell (assuming this Ol' Fart can continue doing track days).

For street-only use, unless you're a dangerous maniac that's trying to be hard on brakes, it appears that CCB rotors could last the life of the vehicle ... or at least long past the failure point of many other major parts.

 

too long to read lol. Did some initial weighing with a scale that might not be as precise and they are all over the weight on the rotor so that’s good news.

might have a sale pending and the gentleman is bringing a more precise scale. If anyone is on the fence for a clean set of these at a very fair price, they might be gone in a day or two.

 

SOLD!

 

That just means they weren't cleaned properly ... a difficult task that's not well specified and is why weighing is still not a good substitute for a Carboteq reading.

If your car wasn't "tracked" extensively, I'd have no doubt that the rotors are in prime condition. Nice to see you sold them.

 

thank you. It was a normal street driven car with mainly highway miles. Definitely a good sale for both sides.