johnwelch

After reading a few of the threads on steering wheel vibration under brakeing, I decided to take some of the advice and clean out the holes in my rotors. I jacked up the car, put it in on jack stands, and started cleaning each hole using a drill bit. After getting about 3/4 of the way done, I came upon a hole that I could not get the bit through. I got out the flashlight and started looking at the rotor to see if I could figure out what was blocking the hole. What I saw was a piece of fairly thick wire bent in a U and wedged in the vent slot. Then I saw the same thing in the next vent over. Am I correct in guessing that these wires were placed as an attempt to balance the rotors?

Terry Adams

No way to balance the rotors. My guess is some kid messed with them, knowing what the result would be. Just to be more clever than to key the car.

Mark in Baltimore

I've never heard of using wire to balance rotors. I'd pull them out.

Glen

Seen them in a number of the rotors it will be a w shaped piece if you pull it out. Sort of a V in the middle with 2 smaller U's on each end if its the same one I've seen. Always have yanked them out when found with no negative side effect. Not sure why they are there but it is my guess they are used to hang the rotor during manufacturing somehow.

kkim

johnwelch,

Could you post a picture of what you are talking about for clarification purposes?

johnwelch

Sorry, Kelly, I've already put the wheels back on. While I can't be sure, Glen's description of the object is pretty close.

Steve Weiner-Rennsport Systems

FWIW,..after some conversations with engineers from ATE and Brembo several years ago, I learned that those little wire clips are there for balancing purposes.

I leave them alone.

johnwelch

And that is just what I will do!

Thanks everyone.

chris walrod

Steve speaketh-da-truth, as usual. Our Brembo as well as our PFC rep has recommended, in the past, rotor spring clips, but mostly for vibration damping.

Terry Adams

Oops. Well, that is why I take my car to the people like Steve who know.

CarmG993

JW, did cleaning the slots w/o the 'w' clip in them cure your problem?

johnwelch

I left the clips in, and there does seem to be a reduction, but I haven't spent a lot of time in the car yet. I should know more tomorrow. I'll post an update then.

Dan993

The wires are definitely balance clips. I have been and continue to be involved in the performance brake business and can attest to this type of balancing. It is not as common as it used to be as mill balancing have become the preferred method. this is where the edge of the rotor is machined or milled to correct the balance.

johnwelch

So, bsaed on my drive in to work today, I am seeing some improvement, but the vibration is still there. One thing I did not do was to try and clean the rotors as some have suggested. If I get adventurous I will try that this weekend.

Traffic53

my car also vibrates under braking. i have the a set of the big reds. my local shop drove it and said they are a bit warped- suggested turning the rotors. has anyone ever turned their cross-drilled big reds?