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rotor issues

mightyimightyi Posts: 73
edited May 2013 in MTB workshop & tech
I've just replaced a pair of shimano 495 centrelock hub wheels with a pair of hope pro ii wheels with 6 bolt rotors. however, I can't get the front or rear discs to locate without rubbing - the front one being particularly bad. it's not a pad alignment issue, i've backed the pads all the way off and they inside pad still rubs. the deore m596 calipers are adjusted as close to the hub the mounting holes will allow, but still not working.

The back one isn't quite as bad as the front (probably helps the back is 160mm, front is 180mm) - but even so i still cant get enough adjustment to stop the pads rubbing heavily.

Has anyone else seen this problem?

Posts

  • nicklousenicklouse Posts: 50,675 Lives Here
    so been and bedded them in yet?
    "Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."
    Parktools :?:SheldonBrown
  • mightyimightyi Posts: 73
    no not yet - if they were both like the rear rotor I'd be inclined to let bed in, but the front rotor is binding pretty heavily, the moment you touch the lever the rotor starts moving over!
  • *AJ**AJ* Posts: 1,080
    What adapters are you using? I've had this issue with cheap adapters before.

    I now buy shimano adapters (use shimano brakes) and not had the alignmemt issue since.
  • mightyimightyi Posts: 73
    *AJ* wrote:
    What adapters are you using? I've had this issue with cheap adapters before.

    I now buy shimano adapters (use shimano brakes) and not had the alignmemt issue since.

    I didn't want to take the risk from the start so i bought shimano adapters for front and rear straight off :)

    since i've changed the wheels i took the opportunity to upgrade the front to 180mm from 160mm - but even on 160 centre locks all round the calipers were almost in as far as they could to allow the rotor to sit properly in the caliper.

    I've just about managed to get the back rotor to run without rubbing, but the front just isn't having it. the forks are brand new Marzocchi Marathon LRs so nothings damaged/twisted/bent either. :(
  • The RookieThe Rookie Posts: 27,810
    Centre aligned calipers?
    Currently riding a Whyte T130C, X0 drivetrain, Magura Trail brakes converted to mixed wheel size (homebuilt wheels) with 140mm Fox 34 Rhythm and RP23 suspension. 12.2Kg.
  • mightyimightyi Posts: 73
    The Beginner wrote:
    Centre aligned calipers?

    That's just the problem - I cant; the adjustment range on the caliper simply isn't enough to get the rotor running down the centreline of the caliper.
  • *AJ**AJ* Posts: 1,080
    If its an IS mount fork you could use a small washer between the brake mount face on the fork and the adapter, to push it a bit closer to the wheel....
  • nicklousenicklouse Posts: 50,675 Lives Here
    mightyi wrote:
    i've backed the pads all the way off and they inside pad still rubs.
    mightyi wrote:
    the calipers were almost in as far as they could to allow the rotor to sit properly in the caliper.


    so they can adjust more?

    and just to be clear- the hub side pad is rubbing and the caliper can not move to the hub any more?

    the wheels were bought new from a shop in the current axle configuration? Qr?
    "Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."
    Parktools :?:SheldonBrown
  • OuijaOuija Posts: 1,386
    Just get a hope disk spacer to go behind the rotor and move it out further from the hub. Some Hope hubs can be a bit narrower than standard hubs, causing the problem your describing, which is why hope made these.

    3288.jpg
  • mightyimightyi Posts: 73
    *AJ* wrote:
    If its an IS mount fork you could use a small washer between the brake mount face on the fork and the adapter, to push it a bit closer to the wheel....

    the front forks are post mount so out of luck there....the rear is IS mount so i can shim that to give some breathing space!
  • mightyimightyi Posts: 73
    nicklouse wrote:
    mightyi wrote:
    i've backed the pads all the way off and they inside pad still rubs.
    mightyi wrote:
    the calipers were almost in as far as they could to allow the rotor to sit properly in the caliper.


    so they can adjust more?

    and just to be clear- the hub side pad is rubbing and the caliper can not move to the hub any more?

    the wheels were bought new from a shop in the current axle configuration? Qr?

    no they are adjusted in as far as they can go now - when i had the 495 hubs with centrelocks on they were in almost as much as they could go then as well - sorry for the confusion!

    yup - hub side pad is rubbing on the rotor and the caliper can't move in any more at all.

    They weren't new wheels, but barely used and i had them checked out by twelve50 bikes in Frodsham before i bought them, who are a hope dealer and they've said there is absolutely nothing wrong with them at all. they came to me with 20mm adapters on and I've fitted new QR adapters instead - I had them out again last night, and made sure the bearings are correctly seated and the QRs are fully located in the hub as well.
  • bennett_346bennett_346 Posts: 5,029
    mightyi wrote:
    *AJ* wrote:
    If its an IS mount fork you could use a small washer between the brake mount face on the fork and the adapter, to push it a bit closer to the wheel....

    the front forks are post mount
    What are the rear forks?
  • The RookieThe Rookie Posts: 27,810
    Bennet, you excelled yourself, WTFH are 'rear forks anyway, that not withstanding MI has already said that
    mightyi wrote:
    the rear is IS mount so i can shim that to give some breathing space!
    Currently riding a Whyte T130C, X0 drivetrain, Magura Trail brakes converted to mixed wheel size (homebuilt wheels) with 140mm Fox 34 Rhythm and RP23 suspension. 12.2Kg.
  • bennett_346bennett_346 Posts: 5,029
    Calm down, i was making a (pretty lame) joke about how he specifically asked what the front forks were, not just what the fork was (like you say there aren't any rear forks so why ask what the "front" forks were?).

    I know sarcasm may not extend to your southern part of the world yet but it is a thing and maybe a quick google search would help you? I am willing to explain the concept if you are still stuck...
  • mightyimightyi Posts: 73
    Ok well an update on this - I removed the "cup and cone" washers from behind the caliper (the ones Shimano supplied with the 180mm post mount adapter) - and managed to get just enough clearance on the caliper to stop it interfering with the rotor....it seems the adapter mating points are not square, consequently causing the caliper to twist outwards. Good work Shimano!!
  • cooldadcooldad Posts: 32,599
    Shimano don't use them - sure you didn't buy Avids?
    I don't do smileys.

    There is no secret ingredient - Kung Fu Panda

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    Parktools
  • davewalshdavewalsh Posts: 587
    mightyi wrote:
    I removed the "cup and cone" washers from behind the caliper
    Don't know what you mean by 'behind the caliper' but the cup and cones should go between the bolt head and caliper, with the caliper then mating directly with the adaptor.
    Blue Pig
    Inbred
  • The RookieThe Rookie Posts: 27,810
    If you don't know what your on about, best not to show it off.....think about what you said and what they would do if used as you dsecribed (hint - fack all)

    Avid have cup and cone between bolt head and claiper and caliper and mount, Shimano shouldn't have them at all!
    Currently riding a Whyte T130C, X0 drivetrain, Magura Trail brakes converted to mixed wheel size (homebuilt wheels) with 140mm Fox 34 Rhythm and RP23 suspension. 12.2Kg.
  • nicklousenicklouse Posts: 50,675 Lives Here
    cooldad wrote:
    Shimano don't use them - sure you didn't buy Avids?
    The Beginner wrote:
    Shimano shouldn't have them at all!

    erm they do on the one of the180mm adaptors Well half of a set.
    $T2eC16d,!zcE9s4g3iF0BQJRR!n7YQ~~60_12.JPG

    http://techdocs.shimano.com/media/techd ... 806955.pdf
    "Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."
    Parktools :?:SheldonBrown
  • bennett_346bennett_346 Posts: 5,029
    The Beginner wrote:
    If you don't know what your on about, best not to show it off.....think about what you said and what they would do if used as you dsecribed (hint - fack all)

    Avid have cup and cone between bolt head and claiper and caliper and mount, Shimano shouldn't have them at all!
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