I don't (yet) have a Bentley manual. Does anyone know offhand the minimum rotor thickness for a R52 - front / rear?

 

If I remember correctly it should be stamped on the rotor.
Steve

 

correct, it is cast into the inner rim of the rotor

GEN1 front minimum (OEM) 20.4mm, rear 8.4

pad thickness minimum 3.0mm

max runout 0.05mm

from Haynes

 

perfect - Thanks!

 

Its always been stamped on the rotor, but the last time I looked at the new JCW it didn't seem to have it. I'll have to look harder next time.

 

Are you thinking of turning the rotors?

Generally rotors are cheap enough that you can replace them with brake pads when the pads wear out.

Just get rotors with a durable finish or painted on the hats so they don't rust.

Solid rotors are fine, slotted are OK, drilled are cosmetic primarily and OK for street use but not for track use- they overheat and crack easily.

 

I looked closer today, its not stamped on the rotor.

 

I found the stamping yesterday. It always used to be on the face of the rotor flange, and it was raised lettering. On the new rotors its around edge of the flange and the lettering looks cut, its not raised and is a lot harder to read.

 

Ms B's '09 R55 got the brake service light and at 53k, I'm doing Akabono front pads this weekend. On a quick preliminary visual once over out in the driveway, I did notice what I would call a big lip on the rotor, or at least unusually larger than I am used to seeing on other cars. Bought it at 19k so would assume original pads and rotors?

I know I can pull it all down for the pad service and mic the rotors then but with my luck, they will mic too thin and then I discover I need rotors too. OK, just pick up some rotors and take them back if I don't need them but what a hassel. I too also expect the two pad sets per rotor too.

Is the seemingly exagerated lip normal on the mini rotors or is it a stupid obvious sign of flat worn out? I could try to mic it on the car but kinda hard to read the spec with the wheel on I'd think.

A coin flip? Buy the rotors just in case and not need them or not buy them only to find out on Sunday I should have. I'll probably be wrong either way as usual but just asking here for some better odds.