A few questions about warped rotors

*DrKlop* · 07-07-2008, 05:57 PM

Just installed brand new Brembo blanks with Hawk HPS. And while bedding the pads, I noticed a dull pulsating sound that seems to be coming from my front right wheel.

The noise is heard only when pedal is pressed relatively hard. (not slammed, but still above average braking force. (on a scale from 1 to 10, where 10 = pedal slammed to the floor with activating ABS. I'd say it happens at 5 and above.)

*All bolts seem to be tight (double checked)
*The problem showed up only after new brakes were installed.
*The pedal does NOT pulsate, it's only the sound.

Do you guys think it's a warped rotor, even though the pedal does not pulsate, and I did all bedding procedures perfectly? If not, what else could be the cause?

If the rotor is indeed warped, would in make sense to resurface it, or I should just get another new rotor? (I was dumb enough not to keep the receipt when I got them - a wile ago. So it would be another $60+.)

I read resurfacing a warped rotor, is only a short term solution since the surface will get uneven after a couple of thousand miles again. Is that even true??

Thanks in advance!

jonmandude · 07-07-2008, 08:06 PM

It is easy to take the rotor to a shop and have them check for warped/resurface.

*BEJAY1* · 07-07-2008, 08:13 PM

Or swap your front rotors L/R and see if the sound moves with it.

*DrKlop* · 07-07-2008, 08:28 PM

hm... thanks, good idea!

Now there's only one question left, if it does turn out to be a warped rotor, would it be advisable to resurface it, or it's better to spend more money but get a good new one?

jonmandude · 07-08-2008, 02:06 AM

That would be depending on how much it is warped. A shop could tell you how far out of spec it is and if turning it would be worth it.

MorpheusZero · 07-08-2008, 06:24 AM

Aren't they selling Brembo blanks on the group deal section for like 35 bucks shipped? If it's the rotor, just get another one.

*DrKlop* · 07-08-2008, 03:03 PM

Just an update: the rotor tuned out to be warped. For now I just brought it to a local shop to resurface it. Depending on how it will behave in the future I will probably replace it.

NisTech · 11-08-2008, 11:19 AM

Quote:

Originally Posted by DrKlop

Just an update: the rotor tuned out to be warped. For now I just brought it to a local shop to resurface it. Depending on how it will behave in the future I will probably replace it.

that means it was dropped on shipping

**Matt93SE** · 11-10-2008, 07:04 PM

It wasn't warped/dropped in shipping. you did it with your driving.. you're not supposed to bed pads in on brand new rotors because the rotors aren't seasoned and stress-relieved through driving yet. it takes 500-1000 miles and a dozen or so heat cycles before the rotors are ready to take that kind of abuse.

you can either have the shop resurface the rotors, buy new rotors, or buy some REALLY aggressive race pads- like Hawk Black or Blue- and run them for 10-15 miles doing a bunch of cold stops, then reinstall your other pads and drive easy on the car for a few hundred miles to finish seasoning the rotors.

the aggressive pads will essentially resurface the rotors for you and then you start over with the other pads.