My story:

Last week installed new slotted DBA (4000) rotors. Bedded with my track pads, Carbotech XP-10's two days before taking to Sears Point for two track days with the Audi Club. At the track, rotors and pads performed great.

I drove home (375 miles) with the track pads still on, but now with only periodic modest braking pressure. I expected this to clean my rotor and get it ready for the OE pads.

Tuesday night back home and swapping out the track pads for my OE Audi street pads, I see a ring of residue on the rotor about 1/8 inch wide, running a full circle around the right side rotor. In some areas it is ever so slightly raised, in other areas I cannot feel that it is raised, but slight discoloration has occurred. The ring appears to be occurring just above the location where the rivet hole on the pad occurs, although the rivets are still below the pad surface by 3/32's or so. Same occurs on the left side, but without any sense of buildup to the touch.

With sand paper, then utility knife blade as a scraper (always in "squeegee" mode, never using the point to pick or scratch) I was able to get the surface smooth to the touch, but still with visible discoloration.

Reinstalled my OE pads. They have good depth of material.

The problem is that under reasonably heavy braking, I'm getting some brake jutter. Around town its not noticeable, but with heavy pressure its there. At the track all braking was smooth and linear.

How can I best remove all traces of the residue that I believe to be causing the jutter? Clearly the track pads didn't get it off when run cool and in sort of an "abrasive" mode. Do I need to pull them and have them turned, or is there a product that can accomplish this? Even though smooth to the touch, if microscopic irregularities are there, would they cause some jutter?

Will continued use wear away any offending material? Should I go through a new bedding process with the OE pads? Is there another culprit at work here?

Thanks in advance for advice.

That will take a minimum of material off and eliminate the judder. Have them resurfaced, not "turned". Running them with the current race pads will probably not fix the judder. Not all race pads will be abrasive enough to remove the judder material. The stuff is stubborn.

The one pad that will take it off is the Hawk Blue, and then you have to really work on it and use the correct "cold pad" procedure.

I had a similar problem with residual track pad deposits and brake shudder. It took about a week of driving with street pads, but those deposits (visible on the rotor at ~7:00) finally disappeared, along with the shudder.

<img src="http://pictureposter.audiworld.com/17157/acid2.jpg">

replace them as necessary. I'm using the same setup as yours and I had the same experience from the New Hampshire Event...'junk' on the rotors, ugly noises. It 'went away' as I drove the car around town. I experienced a much worse scenario with the oe setup years ago, but that's for another show. :p
Don't sand or scrape the deposits as it isn't a very precise control for what you're doing and still can leave high spots.
What you've experienced is fairly common and in many cases is thought to be warped rotors. Patience is the key.
It shall pass. :)

Enlighten us.

Judder doesn't always just go away. I ran mine several months and three track events with brake judder. Finally resurfaced the discs. Should have just resurfaced them first.

And I'm not saying to "turn" them and remove a lot of material. A good machine shop that specializes in discs knows how to resurface a disc without removing a lot of material.

aftermarket brake upgrade.
Remember the entire reason for the upgrade is to add 'robustness' to the system to negate thermal stress, dump the heat and provide stopping power.
Therefore the upgrade should be able to defeat these gremlins. If you got rotor problems after all this, the system that was installed isn't up to par and needs to be reevaluated.
If you resurface a rotor you are jeopardizing this 'robustness' designed into that particular system.
Warp is mostly caused by localized hotspots developed for whatever reason(s). Improper heat treat cycles during manufacturing... or incorrect distribution of the molecular structure of the rotor casting in processing.
Insufficient cooldown on the track will exacerbate these defiencies ( localized hot spots). A "good" rotor will take the heat, but sometimes you leave pad materiel smeared on the rotor surface which is misidentified as (feeling like) a warped rotor until you take a closer look at the surface after it's cooled enough and see this smearing.
In some cases the supplier takes the oe rotor blank and machines slots into it and sells it as a performance rotor...not a good thing and a misrepresentation of the product even if the supplier tells you this...
1. You get what you pay for.
2. Buyer beware.

them you are welcome to use them (i am in NH). they are for the stoptech st-40 calipers. this was the only way i could get the deposits left by the ferrodo ds3500 pads after the last track day. 5 min's of light driving will clean the rotors with these pads and then you can re-bed a new set of pads.