I have 4 DE days on new Zimmerman rotors and P. blacks and the front rotors seem to be warped. The vibration is worse the hotter the brakes get and at the end of the main straights. I bedded the new pads in as per instruction. Have others had any problems with P. blacks? Should Pagid or the supplier do anything about this (I bought the rotors and pads from the same place).

Thanks, Mike

 

I have used Pagid pads for many years, mostly the Orange compound. My last two sets of Pagid Orange made the car feel like you described above. I believe it was pad deposits on the rotor and not actual rotor warpage. In addition to the feeling of vibration, are you experiencing a soft pedal? I did. I just switched Pagid Blacks on the same rotors and have had no issues at all and my hard pedal feeling is back. 993tt rotors BTW.

 

I just installed oranges on 2 month old rotors and experienced similar symptoms. I installed the pagid dark blues with the new rotors (bedded them in) and had no issues. I installed the oranges at the track (did not bed them in) but did not get the vibration until the 3rd track day with them. All track days where at either Summit Point or Watkins Glen (both hard on brakes). I havn't checked the rotors but will do so tommorow. Hopefully it is just pad deposits. I assume that one would use a straight edge to check for rotor warping? Thanks.
BTW....my rotors are Zimmerman as well
Jamie

 

I've used Pagid Oranges, which can have pad material clumping problems, for years, always broken in according to Pagid recommendations, with slotted rotors, and have not had any depositing problems - which do mimic warped rotors - you can read about deposits here. I did read recently where somebody attributed the deposits from getting the pads/rotors too hot, that is, running the pads outside their temperature range. If running a 968, you do have your cooling scoops in place?

I wouldn't get too focused on whether Pagid or the supplier should do anything. You're using racing pads on the track, where, for the most part, there are no warranties. If indeed you have a deposit problem, you can try other pads to see if they'll wear off the deposits. I don't like turning rotors, although that would certainly clean the surface, as that reduces the heat sink capacity of the rotor.

If you use your brakes to stop the car after a run (bad practice in any event as it will help to boil your brake fluid), some have suggested that that can lead to a warped rotor, since the pads are in contact with the hot rotor where the rest of the rotor cools off at a different rate. I'm not sure I buy that, but thought I'd mention it.

 

Get a set of Hawk Blues and run them for a bit and they will clean up the old pad deposits left on your rotors.

 

It should go away eventually or you could get your rotors blanchard ground to get rid of the deposits.

 

I had the same problem, I have been using blacks for some time now. It is not a warped rotor rather the brake dust clogging the holes and sticking to your rotor.

I asked several people and was told to do this and I have never had the problem since. Take a high powered air hose and blow through every hole in the rotor, then take a drill bit (one that is just a tad smaller then the crossed drill hole ) and drill through the hole to make sure all the brake composite is gone. Blow through the top part of the rotor as well. It's a messy job, but it works and keeps you from experiencing the warp rotor feel.

 

I agree with Greg F. and this worked for me just a few weeks ago.

 

I went from the Hawk Blues to the Pagids last year (orange not black) and had the same problem which constantly recurred when the car would be washed and sit between events. I had to rebed the pads at every event. It took away good run time and was a PITA.

I went back to the Hawks (Blues as Greg suggested) and that solved the problem for good. Chances are you do not need new rotors- but I bet you do need either new (Hawk) pads or be prepared to play the rebedding game.

AT WG last year I thought the front end was going to come off the car shook so bad. Nope.... just the pads.....After alternately letting them cool and driving with my foot on the brake they bedded in and were fine.

 

I do have the brake scoops on the car. I have solid rotors not drilled or slotted. I run metal master pads on the street between events. After the 2nd DE I now feel vibration with the metal master pad where I didn't before. I can't see any build-up on the rotor??? Also the rotor is scored pretty badly on the middle of the rotor with the outer and inner 3/4" pretty smooth.

Thanks, Mike

 

Very tmely thread for me, thanks Mike for getting it started. I think I will try the Hawk blues. I think I recall someone saying that the Hawks are very corrosive (have Fikse fm-10's). Is this something to be concerned about?
Thanks.

Jamie

 

When you're blowing the brake dust out of the rotors, make sure you're wearing a respirator or at least a good mask and you're in a well ventilated area. That dust is not very lung friendly.

 

We have switched a lot of people to Hawk Blues for this reason.

 

Jamie,

Talk to Mark in Baltimore as he runs Hawk Blues and has the FM-10s as well.

He bought a power sprayer to deal with cleaning the wheels of the hawk brake dust.

-Skip

 

I use a power washer and Simple Green. Makes cleaning FM10s a piece of cake.