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Old 04-28-2010, 01:32 PM
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bluebee bluebee is offline
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Mein Auto: 02 BMW 525i M54 auto 130K
Originally Posted by hxgaser View Post
Modern brake works not by rubbing the pad against the rotor. The theory is that the pad compound actually gets embedded in rotor. And it is that compound against the same compound that works the brake. That is why the bedding procedure is very important.
Agreed. AFAIK, what we mere drivers call braking "friction" is mainly due to chemical bonds of bedded-brake-on-rotor against brake pad surface breaking and remaking themselves, with heat energy poured out as a result of the friction caused as the bonds break and remake themselves over and over again (covalent bonds IIRC???).

I don't quite understand how chemical bonds breaking and making themselves cause enough friction to stop a speeding BMW E39 - but IIRC, it's all explained in the rebedding PDFs at this thread.

you should run same pad compounds for both front and back
Yup. When I researched how I could compare friction materials in use on my E39, I ran into these experimental testing results for Police-use brake pads, which, IIRC, concluded the single most important factor in stopping power for replacement pads was similar materials front and rear!

- Detailed report by the National Law Enforcement and Corrections Technology Center titled:Replacement Brake Pad Performance Evaluation Project National Institute of Justice/Michigan State Police (dated March 2001)
- Summary report of the Equipment Performance Report: 2000 Evaluation of Replacement Brake Pads for Police Patrol Vehicles (dated February 2001)

So, given that the most important factor may be similar materials front and rear, and bearing in mind the OEM Jurid 187 (fronts) & OEM Textar T4071 (rear) combo, do the Axxis Deluxe crowds recommend Axxis Deluxe on both axles (or just the front which dusts the most in the OEM configuration?

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