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Old 03-27-2018, 06:21 AM   #1
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Brake pad over hanging rotors?

I noticed this weekend while replacing my pads that the pads over hand the rotors by an 1/8 or so (in other words the rotors seems slightly undersized). Is this normal? The pads are seated correctly and pinned.

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Old 03-27-2018, 06:46 AM   #2
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No not normal.

What brand pads and rotors are you using?

Initial thought was maybe not seated correctly but then you wouldn't have been able to get caliper pin back in. Then thought maybe you were shipped S pads accidentally. But IIRC they are also a bit wider so they should not have been able to slot into caliper and again you shouldn't be able to get caliper pin back in.

Maybe wrongly packaged pads? I'd contact seller and have them send corrected ones.

Good luck
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Old 03-27-2018, 08:29 AM   #3
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Usually the pads are fully within the rotor by about 1-2 mm, which is why the rotors develop a lip as they are wearing.
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Old 03-27-2018, 08:34 AM   #4
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or wrong rotors on the car? S and non-S rotors are 'slightly' different diameter.
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Old 03-30-2018, 04:19 AM   #5
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Its got to be the rotors. I just installed new pads his weekend (EBC yellows) and they have the same problem. What brand rotors are you all running?
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Old 03-30-2018, 07:41 AM   #6
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Quote:
Originally Posted by The Radium King View Post
or wrong rotors on the car? S and non-S rotors are 'slightly' different diameter.
+ 1

Perhaps the previous owner/shop must have installed base rotors on an S vehicle?
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Old 03-30-2018, 11:04 AM   #7
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I assume your car is a base car (1997 in your sig). I have a base 986. Running base 987.1 cast hole rotors in front (saves 1lb per corner over oem 986 rotors). Zimmerman 986 drilled rotors in back. Can’t run base 987.1 cast hole rear rotors in back unless you want to give up the parking brake. I have no issues with stock size base pads.

Weight savings is over new rotors. Apple to Apple comparison. Used rotors have material removed, so the weight diff might be closer to 8oz (just a guess)

Last edited by SoloPierre; 03-30-2018 at 12:29 PM. Reason: Clarity
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Old 03-31-2018, 09:13 PM   #8
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pad manufacture error. Was slightly off centered.
I've had this weird vibration/oscillation that got worse over the course or 6+ months. Multiple tire balance/switching to different wheel sets that i had but couldn't get anything consistent. 2 winters ago one day it was so bad I didn't feel comfortable going over 50 driving home on the freeway. Decided to check the pads for some reason and found the outer edge of the pads (about 2 or 3 mm's) that were not worn as it was outside of the rotor on a half worn pad. So the part that was not worn was randomly grabbing the outer edge of the rotor causing vibration/oscillation.
Same rotor has been on 4 sets of pads and that was the only pad that I had issue with. I believe that one was a brembo brand pad.
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Old 03-31-2018, 09:15 PM   #9
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Originally Posted by steved0x View Post
Usually the pads are fully within the rotor by about 1-2 mm, which is why the rotors develop a lip as they are wearing.
In my case it turned out to be that the pad was actually 2-3mm outside of the rotor.

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