Break in rotors?

[biketsai]

I just put on my A8 rotors and the brakes feel weak. I bled the brakes as well. Do i need to do any crazy stops?
Is this common?

[djwimbo]

Worse than stock? They shouldn't feel much different. If you're using stock calipers you really didn't change much other than heat dissipation.

How are the rear brakes?

Proper break in is difficult to explain, but basically be nice for the first week or 200miles.

... FWIW I have slotted rotors all around, and the 12.3" up front, decent pads, and I THOUGHT it stopped well. Tracked it once and learned otherwise. Now my pads are overheated and squeal really bad.

[Nebone]

Very common. What pads?

I've felt this with Mintex and Hawk HPS.

[biketsai]

Im using my old EBC ceramics which had ALOT of life left. So be soft on them?

[djwimbo]

The rotors themselves don't really have a break in period. The pads do, sorry, communication malfunction.

They shouldn't feel like a night and day difference, but I found them to be slightly more touchy.

[Nebone]

Spray some water on the rotors when they are cold and let it sit overnight. That will put some rustiness on them. Drive the car, use the brakes, park it and see if all the rust is gone. The pads might have an uneven wear from the old rotors. I learned to do pads and rotors together, always.

[biketsai]

thanks, ill try that out.

[Nebone]

Or just write on them with a marker.

[biketsai]

Do you think the pads will wear down to the right amount eventually?

[biketsai]

Well actually come to think about it, the rotors ahd a protective coating that all came off.

[onemoremile]

They will given enough pedal pressure and a few good hard stops.

Break in isn't that complicated. You start out with dissimilar materials - an iron rotor and either a metallic or ceramic pad. In order for them to function properly - especially for cold bite - the rotor needs to have some of the pad material embedded in it. This is what the break in process is all about. Check the website of the pad manufacturer and there should be some bedding in or break in instructions.

[20A4Audi1.8t01]

I wanna see pics!!! haha

[onemoremile]

Well actually come to think about it, the rotors ahd a protective coating that all came off.

New rotors have to be washed with dish soap and water or sprayed liberally with brake cleaner before installation. I use dish soap and a green scotchbrite pad.

The rotors are iron which rusts (oxidizes) very quickly. They are protected by either a wax or oil that could otherwise compromise brake performance. Take a great performing brake system and rub wax or oil on the rotors or pads and it will obviously not perform to the same level. If the pads have been contaminated then clean the rotors and pads with brake cleaner and then lay some sandpaper on a flat surface and rub the pad surface on it to get down to virgin material. You can also rub them on a clean concrete surface.

[biketsai]

I wanna see pics!!! haha

Nothing special, just plain rotors, haha

[20A4Audi1.8t01]

oh I thought you bought that one guys with the drilled/slotted no?

[biketsai]

nope

[20A4Audi1.8t01]

true, well im sure youll be posting pics soon enough!

[biketsai]

Lol, did you see my "lowering" thread?

[20A4Audi1.8t01]

yeah I posted in it haha you had the rotors on then?

[biketsai]

nop

[DuviVr6]

maybe u left some air in a brake line !

[Nebone]

Plain rotors are great. onemoremile and I'll tell ya they are better for longer life and don't cause vibrations down the line. You'll like the bigger rotors.

[andyrew]

New rotors have to be washed with dish soap and water or sprayed liberally with brake cleaner before installation. I use dish soap and a green scotchbrite pad.

The rotors are iron which rusts (oxidizes) very quickly. They are protected by either a wax or oil that could otherwise compromise break performance. Take a great performing brake system and rub wax or oil on the rotors or pads and it will obviously not perform to the same level. If the pads have been contaminated then clean the rotors and pads with brake cleaner and then lay some sandpaper on a flat surface and rub the pad surface on it to get down to virgin material. You can also rub them on a clean concrete surface.

Or use Brake cleaner and a rag. Spray the rotors both sides.. However if you didnt do this before you installed your new rotors...

[djwimbo]

I wanna see pics!!! haha

They're really nothing to brag about. When people ask me what's done to my car it's definitely not on the top of the list, and I usually don't mention it unless they ask.

BUT, for giggles ...
Before

After

Wheel on.

[biketsai]

Or use Brake cleaner and a rag. Spray the rotors both sides.. However if you didnt do this before you installed your new rotors...

Did it

[20A4Audi1.8t01]

looks nice DJ

[xraycer2012]

There is a technique out there called bedding the brakes. I just did the A8 brake upgrade about a month ago w/ hawk hps pads. What you do is find a big parking lot and get up to a moderate speed ~40mph and then put about half pressure on the brakes and come to a complete stop 4-6 times. What this does is get the top layer of the brake pad on the rotor, which makes the brakes come alive and work the way they should. It will also get the top layer of coating off the rotor. Be careful however not to apply too much pressure because if you do you will heat up the pad too much and gasses will escape from the pad material, which affects the performance of the pad. Also if you are going from the stock pad to a metallic or ceramic pad the pedal will be stiffer because the pads are made from a stiffer material. Don't worry if they don't feel very good right now. Mine were the same way. Once you get about 150ish miles on them you'll be able to tell they're way better than stock. Hope this helps

[.Mad Hatter.]

here

and here