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Brake Adaptors

minley1minley1 Posts: 126
edited December 2012 in MTB workshop & tech
I currently have XTR M965 IS mount Calipers, a new frame I am looking at is Post mount, does anyone know which adaptor I will need please?

Posts

  • Pm-is (disc size)
  • The RookieThe Rookie Posts: 27,802
    http://superstar.tibolts.co.uk/product_ ... cts_id=359

    Type2 on this page assuming you were using a M965 rear, if you were using a front it would be a 140mm disc and you won't find an adaptor.

    I can do you one cheaper than that, PM me if you're interested.
    Current steed - Whyte T129, 2013 frame, mongrel Revelations, Giant dropper, Stans S1 wheelset. 12, Magura Trail Sport brakes, 1x11. 12.8Kg
  • cobbacobba Posts: 282
    http://superstar.tibolts.co.uk/product_info.php?cPath=57&products_id=359

    Type2 on this page assuming you were using a M965 rear, if you were using a front it would be a 140mm disc and you won't find an adaptor.

    ?

    That's for fitting a PM caliper on a IS frame.

    The OP has a IS caliper and wants to fit it to a PM frame.

    An adapter like the following would be needed.

    http://clee-cycles.co.uk/esite/P1043/product

    These adapters are for the 'Front' but they'd probably be able to be used on rear post mounts.

    If you were to try one of these adapters you have to take into account what size post mounts were on the frame, I'm not sure if the 160mm adapter will work with 5" post mounts.

    You'd also have to take into account what size the IS caliper is.

    A 160mm front IS caliper is the same as a 140mm rear IS caliper
    A 180mm front IS caliper is the same as a 160mm rear IS caliper.

    Might be time to buy some new PM brake calipers.
  • minley1minley1 Posts: 126
    Thanks for the reply's, I guess I will have to try a couple and see, all depends of course on if I get the frame or not.
  • The RookieThe Rookie Posts: 27,802
    cobba wrote:
    http://superstar.tibolts.co.uk/product_info.php?cPath=57&products_id=359

    Type2 on this page assuming you were using a M965 rear, if you were using a front it would be a 140mm disc and you won't find an adaptor.

    ?

    That's for fitting a PM caliper on a IS frame.
    Total brain fade....ta for the correction
    Current steed - Whyte T129, 2013 frame, mongrel Revelations, Giant dropper, Stans S1 wheelset. 12, Magura Trail Sport brakes, 1x11. 12.8Kg
  • The RookieThe Rookie Posts: 27,802
    You can get IS to PM adaptors, but they destroy the whole point of an IS caliper (lighter than PM plus adaptor) or PM mounts on the frame (no need for a heavy adaptor)....best is to swap the caliper for PM, in fact you could probably find someone happy to swap with you.

    I have an XT M765 caliper going spare that would be ideal....
    Current steed - Whyte T129, 2013 frame, mongrel Revelations, Giant dropper, Stans S1 wheelset. 12, Magura Trail Sport brakes, 1x11. 12.8Kg
  • 02gf7402gf74 Posts: 1,168
    IK preferred IS callipers, for the reasons you mentioned but they seem to have been superceded by POST mount, there are very few forks now with IS, POST Being far more popular.
  • minley1minley1 Posts: 126
    cobba wrote:
    http://superstar.tibolts.co.uk/product_info.php?cPath=57&products_id=359

    Type2 on this page assuming you were using a M965 rear, if you were using a front it would be a 140mm disc and you won't find an adaptor.

    ?

    That's for fitting a PM caliper on a IS frame.

    The OP has a IS caliper and wants to fit it to a PM frame.

    An adapter like the following would be needed.

    http://clee-cycles.co.uk/esite/P1043/product

    These adapters are for the 'Front' but they'd probably be able to be used on rear post mounts.

    If you were to try one of these adapters you have to take into account what size post mounts were on the frame, I'm not sure if the 160mm adapter will work with 5" post mounts.

    You'd also have to take into account what size the IS caliper is.

    A 160mm front IS caliper is the same as a 140mm rear IS caliper
    A 180mm front IS caliper is the same as a 160mm rear IS caliper.

    Might be time to buy some new PM brake calipers.

    I ordered the KCNC one above, it does not appear to suit, the caliper sits a the wrong angle, struggling with this.
    If I need to get a new caliper, the PM XTR seem rare unless you get the latest Race or Trail model.
    Ideally would like XTR as I have recently bought the M975 Levers and am loathe to change the whole set up, any suggestions?
    Someone mentioned that I may need to go up a disc size, but it still looks like the caliper would be at the wrong angle.
  • cobbacobba Posts: 282
    Take some photos so we can see what the brake looks like on this adapter.
    Putting a IS caliper on the rear of a bike that has post mounts isn't something that you hear of very often.
    Some close up photos that show some detail would be useful for future reference.
    Someone mentioned that I may need to go up a disc size, but it still looks like the caliper would be at the wrong angle.

    180mm Front / 160mm Rear IS brake caliper + 160mm adapter + 6" post mounts = 180mm rotor
    160mm Front / 140mm Rear IS brake caliper + 160mm adapter + 6" post mounts = 160mm rotor

    There's only 10mm difference between the radius of a 160mm rotor and a 180mm rotor.
  • AnonymousAnonymous Posts: 79,667
    You need an A2Z adaptor to convert IS to post,
    Had that issue on my old set of Xtr in the end sourced the above adaptor.
  • cobbacobba Posts: 282
    You need an A2Z adaptor to convert IS to post
    or the KCNC adapter that I linked earlier which the OP has already bought.

    The A2Z AD-PMF74, is the same as a KCNC 180mm PM to IS adapter which I put up a link to.
    A2Z also has the AD-PMF203 which is the above A2Z adapter but it comes with 10mm spacers to make it a 200mm adapter, it basically the same as a KCNC 200mm PM to IS adapter.
    http://www.a2zcomponents.com/02products_04adapter_03.html

    Hope also have a PM to IS adapter, the HBSM20H, this adapter is also the same as a KCNC 180mm PM to IS adapter.
    http://www.chainreactioncycles.com/Models.aspx?ModelID=13735

    Ashima also make this type of adapter in 180mm and 200mm sizes.
    http://www.ashima.com.tw/Disk-Brake-Adaptors.html

    KCNC is the only company that has this type of adapter in the 160mm size.
    A 160mm adapter means that you don't have to upsize the rotor, a 160mm caliper = a 160mm rotor and a 180mm caliper = a 180mm rotor.
    * The 160mm KCNC adapter won't work on all PM forks and won't work with IS brakes.

    a 180mm adapter + 6" Post Mounts + a 180mm Front / 160mm Rear IS brake caliper = a 200mm rotor.
    a 180mm adapter + 6" Post Mounts + a 160mm Front / 140mm Rear IS brake caliper = a 180mm rotor.
    a 200mm adapter + 6" Post Mounts + a 180mm Front / 160mm Rear IS brake caliper = a 220mm rotor.
    a 200mm adapter + 6" Post Mounts + a 160mm Front / 140mm Rear IS brake caliper = a 200mm rotor.

    IS Brake Caliper Differences: BR-M960 160F/140R & 180F/160R Brake Calipers
  • The RookieThe Rookie Posts: 27,802
    Any shimano banjo hose connection caliper will work, so M765 XT for example, I use an XTR rear caliper with XT lever as I have an IS frame.
    Current steed - Whyte T129, 2013 frame, mongrel Revelations, Giant dropper, Stans S1 wheelset. 12, Magura Trail Sport brakes, 1x11. 12.8Kg
  • cobbacobba Posts: 282
    Post some photos of the brake mounted on the KCNC adapter.
  • minley1minley1 Posts: 126
    Having had a good look again, the Calliper fouls the frame as does the adaptor, without taking material of either it is not going to fit, took it to the LBS and they agreed.
    Have ordered a new XTR M985 PM calliper from them.

    Thanks for all the advice, as always a wealth of knowledge on here.
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