Rebedding brakes?
 

Is there a way of starting over and trying to bed the brakes again?

This is on my BMW, I put Pagid pads (street compound) with a ATE rotors all the way around. I tried bedding them by letting them heat up and doing some controlled stops. Now at halfway through braking the steering wheel shudders, I apply more brake and that goes away and brakes as it should. Should i remove the pads, take a scotch brite wheel to them and start over? Can I?

Anyone tried it?

Sounds like you glazed over the pads and rotors. I think you are on the right path towards a fix. You will also want to apply brake cleaner and a fine grit sandpaper to the rotors.

Keep in mind that Pagid pads are pretty sensitive to the bed in process. Go to their website for the instructions and follow them closely.

I use a regular piece of coarse (150) sandpaper laid on the garage floor and just run the pads back and forth over it. Deglazes and levels them in 30 seconds.

The info I found at this site helped me: http://www.stoptech.com/tech_info/wp...contents.shtml This is a good read as well: http://www.stoptech.com/tech_info/wp...rakedisk.shtml

What speeds were you doing this at? Heating up street compound pads too much will cause them to "melt" just a little and leave deposits on your rotors which cause the vibration you speak of. My friend just made that mistake on his '99 M3... took street pads to a track event with RA1s and now his car feels like its going to fall apart whenever he brakes.

To brak ethem in I did a few stops from 35 to 10 and then 50-20 and 60-30. All was sweet with them for the last 3-4 weeks. Just a couple days ago they gave the steering wheel a wobble halfway through slowing down for a stop. Seems to go away as I press the pedal harder.

Basically, once your brakes are bedded properly, you can usually get them back shipshape with a couple hard stops then a cooldown. Worst thing you can do is sit stopped while things are still extremely hot with the pads clamped hard on the rotor. There's more tendency to do this in auto cars, IMHO, for example at that first red light at the bottom of the twisties.

Did you put new pads and rotors on at the same time? A basic rule is to always bed new pads with used rotors and new rotors with used pads.

These are some excellent articles... Good find!! :cheers:

I've never had a problem bedding new pads and rotors together. I'd prefer not to do a brake job three times before its bedded properly. That just sounds ridiculous. You really think when you take your car to a shop to get rotors and pads they do it that way. I have a hard time believing you have to do this.

it's not like it wobbles through the whole motion. ANd when I apply more the 50% braking the wobble goes away and is as smooth as normal.

I am sure that you can do the job differently, but it will only be done correct one way. And the only shop I have worked at does it that way (DEVEK). When reading the instructions it says to do so for most race pads.

If you put new pads on new rotors the rotors will get a lot of pad residue where it expands the most wich is over the walls of the ventilation passages of the disc. This uneven spread of low friction zones leads to the vibrations. You can probably get away with scrubbing the disc with sandpaper to get away with it but it is much easier to just put the pads on first and bed them with the old rotors and then swap the rotors.

These are street compound pads though.

You can bed in a new pad/rotor combo, you just have to be more careful to avoid coming to a complete stop while everything is hot.