Go Back   986 Forum - The Community for Porsche Boxster & Cayman Owners > Porsche Boxster & Cayman Forums > Performance and Technical Chat

Post Reply
 
LinkBack Thread Tools Display Modes
Old 03-27-2018, 05:21 AM   #1
Registered User
 
truegearhead's Avatar
 
Join Date: Jul 2011
Location: Richmond, VA (The Fan)
Posts: 978
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.

__________________
1997 Boxster 4.2L Audi V8 Bi-Turbo
2003 911 C2
NASA HPDE Instructor
truegearhead is offline   Reply With Quote
Old 03-27-2018, 05:46 AM   #2
Registered User
 
Join Date: Nov 2006
Location: In the garage...
Posts: 1,702
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
__________________
"Cool Prius!"
- Nobody
Burg Boxster is offline   Reply With Quote
Old 03-27-2018, 07:29 AM   #3
Registered User
 
steved0x's Avatar
 
Join Date: Dec 2012
Location: FL
Posts: 4,143
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.
steved0x is offline   Reply With Quote
Old 03-27-2018, 07:34 AM   #4
Registered User
 
The Radium King's Avatar
 
Join Date: Apr 2010
Location: Canada
Posts: 3,121
or wrong rotors on the car? S and non-S rotors are 'slightly' different diameter.
The Radium King is offline   Reply With Quote
Old 03-30-2018, 03:19 AM   #5
Registered User
 
truegearhead's Avatar
 
Join Date: Jul 2011
Location: Richmond, VA (The Fan)
Posts: 978
It’s 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?
__________________
1997 Boxster 4.2L Audi V8 Bi-Turbo
2003 911 C2
NASA HPDE Instructor
truegearhead is offline   Reply With Quote
Old 03-30-2018, 06:41 AM   #6
Registered User
 
Join Date: Dec 2009
Location: Orange County, CA
Posts: 1,848
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?
Gilles is offline   Reply With Quote
Old 03-30-2018, 10:04 AM   #7
Registered User
 
Join Date: Oct 2011
Location: SoCal
Posts: 66
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 11:29 AM. Reason: Clarity
SoloPierre is offline   Reply With Quote
Old 03-31-2018, 08:13 PM   #8
Registered User
 
Join Date: Nov 2009
Location: PA
Posts: 170
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.
geetee is offline   Reply With Quote
Old 03-31-2018, 08:15 PM   #9
Registered User
 
Join Date: Nov 2009
Location: PA
Posts: 170
Quote:
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.

geetee is offline   Reply With Quote
Post Reply



Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On
Trackbacks are On
Pingbacks are On
Refbacks are On




All times are GMT -8. The time now is 11:02 AM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2024, vBulletin Solutions, Inc.
Content Relevant URLs by vBSEO 3.6.0
Copyright 2024 Pelican Parts, LLC - Posts may be archived for display on the Pelican Parts Website -    DMCA Registered Agent Contact Page