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Warped brake discs.

scale20scale20 Posts: 1,300
edited March 2008 in MTB workshop & tech
Hi all,

I have the standard 185mm brake discs on my '08 Trek EX9 and after a handfull of rides from new the discs have warped or buckled, Not a lot just enough for it to rub on the calipers and annoy the hell out of you to the point where you want to smash em to bits!. The bike has never taken a hit or been in a crash so I'm a little stumped why they are like that.

I have taken the discs off and layed them flat on my kitchen worktop and you can see a tiny buckle not even a mil. I have had a tinker and managed to stop them rubbing as much, but for how long?

Is this a common thing with the bigger discs? due to the exessive heat during braking?

Are there a better, higher quality discs out there that i can change them for?

Cheers, Martin
Niner Air 9 Rigid
Whyte 129S 29er.


  • nicklousenicklouse Posts: 50,675 Lives Here
    sounds more like the calipers are not aligned correctly. new brakes need to settle in.

    And the bike will need to go for its first service after a few weeks to have these tings tweeked out.
    "Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."
    Parktools :?:SheldonBrown
  • scale20scale20 Posts: 1,300
    Ive only had the bike since Jan, so the 1st service is a while away yet.

    I have re-aligned the calipers, and the disc, more the front, is definatley slightly warped

    I have never had this problem with the hope's on my scott.
    Niner Air 9 Rigid
    Whyte 129S 29er.
  • pittponypittpony Posts: 1,057
    A lot of places recommend a first service after a month or 6 weeks if you ride regularly. Lots of things to settle in on a new bike so a lot needs adjusting farily quickly
  • god1406god1406 Posts: 554
    a service after six weeks?? That sounds like a ploy to get a bit more money out of you.

    The disks on all my bikes rub a little bit, you just align them best you can and get over it.

    'one nanosecond- the amount of time in which there is nothing wrong with my bike'
  • silly question, but are all the bolts holding the disc on torqued correctly??

    might also be worth taking off disc, wiping down hub flange and disc and putting back on. Dunno if some grit has caused the disc not to sit on the hub squarely.

    while you're about doing that you could put disc on a flat surface and see if it really is warped
    Train hard, ride easy
  • pittponypittpony Posts: 1,057
    god1406 wrote:
    a service after six weeks?? That sounds like a ploy to get a bit more money out of you.
    The first service should be free at any good LBS
  • scale20scale20 Posts: 1,300
    Couldnt stand it anymore, done all the above, thanx guy's. Its in getting hope's all round fitted!
    Niner Air 9 Rigid
    Whyte 129S 29er.
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