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  1. #1
    nnn
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    Using rear BR-M755 calliper up front

    I've been looking around for some info and struggled to find anything definitive. I know by standard rear IS mounts are 20mm more than front mounts, so 160mm rear calliper becomes a 180mm on the front.

    With hope brakes you just buy the calliper number that you need and stick it on the front or rear. The problem with M755s is it seem the front and rear callipers have a slightly different design as seen in the technical drawings here http://www.fa-technik.adfc.de/Herste...himano/BR.html

    So my question is is it still ok to run the rear calliper up front and would it actually be 180 or does it stay as 160 due to the different design ?

  2. #2
    Nightriding rules SuperModerator
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    it will be 180mm up front...no problem...

  3. #3
    nnn
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    Great! I'll write back once it's sorted out in case anything goes wrong.

  4. #4
    Meh.
    Reputation: XSL_WiLL's Avatar
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    Yup. No problems with a 180mm rotor.

  5. #5
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    Actually, a rear 755 caliper mounts directly on to a IS mount and will fit a 200mm rotor w/o adaptors. The rear has a longer offset than the front like you had mentioned.

    I'm 100% certain since I've owned 5 sets of 755/756 XT brakes and had the Hope Mono 4 with the same front caliper dimensions as my XT rear that fits on my 888 IS 8" mount with only shims..

    A rear XT is the same as a #8 Hope caliper I believe.

  6. #6
    Nightriding rules SuperModerator
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    Quote Originally Posted by MonkeyBidnezz
    Actually, a rear 755 caliper mounts directly on to a IS mount and will fit a 200mm rotor w/o adaptors. The rear has a longer offset than the front like you had mentioned.

    I'm 100% certain since I've owned 5 sets of 755/756 XT brakes and had the Hope Mono 4 with the same front caliper dimensions as my XT rear that fits on my 888 IS 8" mount with only shims..

    A rear XT is the same as a #8 Hope caliper I believe.

    if you say so.... however the IS standard has a 10mm radius offset difference from the front to the back, so if it does work with a 160mm in the rear it would have to be in a really weird position to give 200mm up front....

  7. #7
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    Here's a pic of the my old Hope set up mounted to the IS mounts on my 888 with 8" rotor. The caliper is identical to the rear XT caliper in terms of spacing.


  8. #8
    Nightriding rules SuperModerator
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    thanks for the pic..... that mount does seem awfully far from the axle (maybe the angle of the pic), but I can see how a shorter lower arm could give any smaller size....

    I still stand on the IS difference though....

  9. #9
    Meh.
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    I duno... the XT arm does not seem to be as long... and if it were... caliper position would be pretty funky on the rear. I've got a set of these 4 pots... And I think I would've noticed. And I do know for a fact that the front 160mm caliper mounted on the rear takes a 140mm rotor.




  10. #10
    nnn
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    ^Sweet pics !!

    Yeah I think because of the weird offset on the rear calliper the diffenrece would not be the same as the front calliper so maybe it does add 40mm in any case in a couple of weeks when my fittings arrive from Shimano we will know for sure

  11. #11
    Meh.
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    You could test fit it now to try and see. I don't think that the offset of the XT caliper is the same as the Hope.

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