jpar002

I just installed Centric drilled/slotted rotors on my 04 545i w/ stock pads last Saturday. I'm hoping they don't eat through the pads too quick.. also i noticed the rear rotors don't have a full contact pattern no the rotors yet. Maybe i need to bed them?

socale39

Yes you will need to bed them. I had the same problem on the front and it took me 2 bedding processes to get full pad contact.

sluggoslinger

I had the stoptech slotted cross drilled roters and axis pads installed on my 05' 545 and i've had alot of wheel shake when braking. It seems to be getting worse. Its driving me insane and now that i'm starting to hit the mountains every weekend, the decent sucks. I don't trust the car to brake smoothly going into corners. When braking hard, you can hear them biting... When they are cool its fine but braking from anything over 60 when they are hot causes alot of vibration.

The other day, the kid across the street told me that the roters were installed backwards. If you look at the car, the slot at the top of the rotor is tilted towards the front. I've put about 5K-10K miles on them since they were installed.

Are they installed incorrectly? Could this be damaging them?

Howitzer

This means that your rotors were not properly broken in. The issue is that there is a layer of brake pad material on the rotor that is thicker than other spots. I am not sure if this can be fixed but perhaps the only way is to try the break-in process again. 8 to 10 violent hard near-stops from 60 to 10 mph, never stopping. You might be able to burn off that layer and smooth them out again. Otherwise you'll have to resurface the rotors.

Direction of rotors is not the cross-drilled part but the vents in between the two discs. They need to be "catching" the air as the wheel turns to cool them. If they aren't, they're installed backwards. But if yours are cross-drilled and slotted its a no-brainer. Make sure the slots are going with the grain of the wheel spin to see if they're installed wrong.

sluggoslinger

So by with the grain of the wheelspin, you are saying that they are not installed properly? Currently the slot at the top of the rotor is tilted towards the front of the car.

Thanks fos clarifying...

socale39

I had excessive shaking just like you are stating and it took a good 3 brake bedding processes to eliminate it. Each process is 0-60-0 with hard braking for about 6-8 times. I even did a few 0-80-0 runs to make sure. Be sure to do normal driving to heat up the brakes before doing the process. Also, you should at least smell brake pad by the last stop or have some smoke.

Howitzer

See this illustration? This is how your cross drilled and slotted rotor should be installed:

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See the image below? The vents between the discs must catch the air as it spins:

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jordan23junkee

they look awesome. I purchased mine months ago , just havent been motivated to do it. Now that I see your im finally having my mechanic do them. He's only charging $100 which sounds good right?

525iEnjoy

Socale's rotors are directional vaned rotors with slots and drilled. When installing directional vaned rotors you cant install by slot or drill direction you must install by vane direction. It is possible they're on backwards but the installer should know and also the vendor who sold you the rotors would have told you. Um the new rotors do come with coating for rust prevention so bedding is needed with new and old pads. Also Old pads used with new rotors will need a bedding process.

1. make a quick call and see if your rotors have curved vanes"directional".

2. based on one , try re-bedding.


if your heating up rotors and pads and the rotors aren't getting airflow warping can occur.

Howitzer

Righto, and my R1 Concept rotors do not have vents in the center that are directional at all; they go straight up and down like OEM.