I just found a circle of blue glaze on my brake disk. It is on both sides. It looks a bit shining with blue glaze. Does anyone know what happened? Do I have to replace the rotors?

 

yeah are they new?did you break em in. sounds like what would happen if they got hot? but you cant see sheeit in the pic.

 

I bought the bbk new but there were some problems with the fitting at first. The store did a few modification to the disk as well as the pad. Then it was ok. But after I used it for one month I found the glaze. It is like you have oil spill on the disk and you can see the shining light from reflection. I check everyone else's disk there is nothing like that. A normal disks have plain smooth shinning surface without any mark. Someone said it is caused by overheating but I am not sure.

 

The surface should be shinny. That looks as though the pad is only contacting in that ring. You better pull that caliper and check to see fitment and if there is foreign material on the pad.

 

although i dont have the info in front of me, and its hard to know what you're seeing by that pic,...

i recall in one of stoptech's whitepapers on bedding brakes that when they are properly bedded you are likely to see a blue tint to the rotor. having just installed their rotors, axis ultimate pads, and other things... and after bedding it in, i noticed a light bluish ring on the rotor.......

 

Thanks guys. In fact I noticed today some part of the blue glaze has gone away. Seems like it is not some kind of permenant damage. Hopefully it will go away completely later.

 

WTH, you had to modify your BBK?
Are they supposed to fit w/o mod in the first place?

 

Steel will turn blue when heated.

Looks like the pads were not perfectly set and someone tried to brake hard none the less. Braking on part of the rotors, overheating it a bit.

It shoud shave off with time.

 

Yes and I was pissed! But I had the kit shipped all the way from US to Taiwan and too difficult to return. Had to deal with it myself!

 

I have a blue ring all the way around the middle of my front rotors too! I just noticed today. I thought I warped my rotors about a month ago and started a thread about it. https://my350z.com/forum/brakes-and-suspension/239043-warped-my-brembo-rotors.html
Someone told me to re-bed them. Basically, do 80mph-10mph appx 10 times in a row. Sounds dumb, but you have to read the process as described by StopTech. Well, I was unable to find any place in OC to do 10 runs of this type.... So I didn't. Now my rotors have turned blue!! Can anyone help?

 

The rotors will turn blue if they are heated up and pad material is applied to the rotor(as mentioned in shanecrosby's thread). The shaking comes from an inconsistent deposit of pad material. The rotors turning blue in your case means that at one point, you got the brakes hot enough to transfer the material onto the rotor, but unevenly. When you do a Bed-In procedure with new pads, a small amount of the pad material (blue-ish hue) is transferred EVENLY onto the rotor as the pad heats up, which is why you have to do the 60-15mph stops about 6 times (or until fade appears). If hard braking occurs once for a longer than normal period of time, it will only deposit on certain spots on the rotor. After the bed in procedure is completed, the brakes will work their best. Once you do a full Bed-in, you will be "filling in the blanks" on the rotor with pad material.