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rumatt · 08-13-2018, 01:56 PM

I'm reading Zimmermann's web site regarding "warped" rotors.

https://www.otto-zimmermann.de/en/se...arpedbrakedisc

1. What they describe sounds like exactly what I have. It gets worse over time, and as the brakes heat up.
2. They say to give up and start over with new rotors

"With an increasing temperature, the cementite will build up and simultaneously penetrate deeper into the brake disc material. [...] This can only be remedied through an exchange of the brake discs and brake pads."

3. It is caused by improper "run in". And their run-in does not involve hard braking

"Violent or shock-braking should be avoided during the first 300 km of travel after the change of the brake discs."

But instead: "30 brake applications from a medium velocity (approx. 100 km/h) with a moderate deceleration"
https://www.otto-zimmermann.de/en/se...ml#runinnotive

Conclusion I think I bed them too hard too soon and they are now fcuked. Not only did I include hard bedding (after gentle bedding to warm them up) but I probably went over 60mph. Which Zeckhausen says explicitly not to do.

08-13-2018, 01:56 PM	#45
rumatt Mugwump Join Date: Oct 2003 Carmudgeonly Ride: E46 330i, Chevy Colorado, Tesla Model 3 Location: NY Posts: 17,475	I'm reading Zimmermann's web site regarding "warped" rotors. https://www.otto-zimmermann.de/en/se...arpedbrakedisc 1. What they describe sounds like exactly what I have. It gets worse over time, and as the brakes heat up. 2. They say to give up and start over with new rotors "With an increasing temperature, the cementite will build up and simultaneously penetrate deeper into the brake disc material. [...] This can only be remedied through an exchange of the brake discs and brake pads." 3. It is caused by improper "run in". And their run-in does not involve hard braking "Violent or shock-braking should be avoided during the first 300 km of travel after the change of the brake discs." But instead: "30 brake applications from a medium velocity (approx. 100 km/h) with a moderate deceleration" https://www.otto-zimmermann.de/en/se...ml#runinnotive Conclusion I think I bed them too hard too soon and they are now fcuked. Not only did I include hard bedding (after gentle bedding to warm them up) but I probably went over 60mph. Which Zeckhausen says explicitly not to do. Last edited by rumatt; 08-13-2018 at 03:55 PM.