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  1. #1
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    Switching from ELixir to Guide RSC what Caliper bolts ?

    Switching from Elixir CR to Guide RSC - what Caliper bolts do I need ?
    this is a 2012 Cannondale Flash29 Carbon frame with 180mm front and 160mm rear rotors.

    The old bolts at the rear caliper are 45mm at front of the caliper and 40 mm at the rear - way to long so I have to use lots of CPS
    The RSC calipers are the model year 2016.
    Pretty sure the calipers are not CPS type.

    Switching from ELixir to Guide RSC what Caliper bolts ?-cid_696299893114616779686442.jpg

    Thanks
    S.C. TB2
    Flash29C2
    Niner One9 SingleSpeed RDO fork
    Supersix Evo 1 Hi Mod D/A

  2. #2
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    You need one set of CPS washer above each caliper mtg tab due to the bolts not being perpendicular to the tabs when using an adapter. Bolts need to be long enough so that there is at least 9mm of thread engagement.
    Do the math.

  3. #3
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    Switching from ELixir to Guide RSC what Caliper bolts ?-10-13-2018-1-08-42-pm.jpg


    I was referring to the 2 different styles of bolts I can see online.
    Any reason style "B" will not work with my configuration ?

    I really would like to get rid of all these CPS washers if possible.
    S.C. TB2
    Flash29C2
    Niner One9 SingleSpeed RDO fork
    Supersix Evo 1 Hi Mod D/A

  4. #4
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    Quote Originally Posted by StumpyElite2010 View Post
    Pretty sure the calipers are not CPS type.
    Correct.

    The old bolts at the rear caliper are 45mm at front of the caliper and 40 mm at the rear - way to long so I have to use lots of CPS
    You need bolts that are 5mm shorter then what you currently have on the 20mm/180mm post mount adapter.

    Bolt lengths are shown here: https://www.sram.com/sites/default/f...ns_rev_c_0.pdf


    Quote Originally Posted by StumpyElite2010 View Post
    I really would like to get rid of all these CPS washers if possible.
    Washers are needed above the caliper with the 20mm/180mm post mount adapter, other brands use the same setup with this type of adapter too.

    Example: http://si.shimano.com/#/en/SI/8170A

    Switching from ELixir to Guide RSC what Caliper bolts ?-p4pb15830280.jpg

  5. #5
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    Yeah, if you have post mount adapters with only 2 bolts, you cannot flat mount them. You have to use cps washers. There are companies that make +20mm adapters that boot to the post mount and have separate mounting holes for the caliper and in that case you could just use bolts. Those are the kind I prefer as Iím not a huge fan of cps where I can get rid of them.
    For example, all the Hope +20mm adapters are 4 bolt.

  6. #6
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    Having used both, my personal preference is CPS washers on the top of the caliper tabs to using 4 bolts.
    Do the math.

  7. #7
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    Technically, I don't think these cup and cone washers can't be called CPS (Caliper Positioning System) washers if they're only used above the caliper.

    When these washers are used above and below the caliper, you can adjust the angle that the caliper is mounted, when they're only used above the caliper, they don't allow the caliper to be mounted on a different angle to the brake mounts, they only allow a bolt to properly tighten down on a caliper when it isn't perpendicular to the bolt.

  8. #8
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    The convex washer must be spherical, not conical, in order to work. The cup (concave) washer could be either and still work. These are them same as one pair used on most V-brake pads. The other pair have a taller concave washer to adjust spacing if necessary. CPS rolls of the tongue and keyboard easier than either cup and cone washers (with the erroneous cone) or the correct cup and spherical washers, IMO.
    Do the math.

  9. #9
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    Quote Originally Posted by cobba View Post
    Correct.



    You need bolts that are 5mm shorter then what you currently have on the 20mm/180mm post mount adapter.

    Bolt lengths are shown here: https://www.sram.com/sites/default/f...ns_rev_c_0.pdf




    Washers are needed above the caliper with the 20mm/180mm post mount adapter, other brands use the same setup with this type of adapter too.

    Example: Manuals & Technical Documents
    That makes sense !
    Looks like this is my configuration
    Name:  10-14-2018 9-37-14 AM.jpg
Views: 19
Size:  17.7 KB

    Now, where do I get this specific length bolts ?
    S.C. TB2
    Flash29C2
    Niner One9 SingleSpeed RDO fork
    Supersix Evo 1 Hi Mod D/A

  10. #10
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    Quote Originally Posted by StumpyElite2010 View Post
    Now, where do I get this specific length bolts ?
    Got a bench grinder?

    That'd be the easiest way to get bolts that are 5mm shorter.

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