Flat convert to drop -disc caliper compatibility issue
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  1. #1
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    Flat convert to drop -disc caliper compatibility issue

    I have a specialized Sirrus Comp Carbon circa2012, and Iíve endeavored to convert flat to drop bars. So I bought tiagra brifters 2x10 for hydraulic brakes. The specialized originally came with Tektro Gemini brakes and Iím finding the caliper mounting bolts spacing and diameter are different with the new tiagra calipers. What the heck!! Whatís the solution here?
    Thanks in advance!!

  2. #2
    'brifter' is f'ing stupid
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    Quote Originally Posted by 1robertpost View Post
    I have a specialized Sirrus Comp Carbon circa2012, and Iíve endeavored to convert flat to drop bars. So I bought tiagra shifters 2x10 for hydraulic brakes. The specialized originally came with Tektro Gemini brakes and Iím finding the caliper mounting bolts spacing and diameter are different with the new tiagra calipers. What the heck!! Whatís the solution here?
    Thanks in advance!!
    ftfy.

    I'm guessing your old calipers are post mount and the new Tiagra calipers are flat mount.
    #promechaniclife

  3. #3
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    Thanks for that! You are correct. Now Iím trying to learn what post mount calipers are compatible with my new Tiagra BR 4720 brifters. Iíve spent hours online with no success.

  4. #4
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    https://www.assolutions.ca/flat-moun...adapter-guide/

    I just went through the reverse, flat mount fork, old post mount calipers. Bought adapters on ebay.

  5. #5
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    Glad you found a solution! Unfortunately their product needs more clearance than my frame allows. Now Iím searching for post mount calipers compatible with the Tiagra BR 4720 brifters. Oy!

  6. #6
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    Quote Originally Posted by 1robertpost View Post
    Glad you found a solution! Unfortunately their product needs more clearance than my frame allows. Now Iím searching for post mount calipers compatible with the Tiagra BR 4720 brifters. Oy!
    Good times eh? Trying to build a bike up using parts on hand in this era of nothing-fits-each-other-anymore is unbelievably frustrating.

  7. #7
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    It sure is! Give me 1980-2005 bikes and Iím good. And I should just stick to steel too.

  8. #8
    'brifter' is f'ing stupid
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    Quote Originally Posted by 1robertpost View Post
    Glad you found a solution! Unfortunately their product needs more clearance than my frame allows. Now Iím searching for post mount calipers compatible with the Tiagra BR 4720 shifters. Oy!
    Shifters. Please...for love of all that is good...shifters.
    #promechaniclife

  9. #9
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    Iíll never say/type brifters again if you provide the solution- what post mount Shimano calipers will be compatible with said ďShiftersĒ!

  10. #10
    'brifter' is f'ing stupid
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    I told you already. Your frame is post mount. Modern road/gravel calipers are flat mount. You've never said what size rotors you have which is essential to know. Google is wonderful for finding stuff, give it a try.
    Or reply w/ your new rotor size and what size rotors were on your frame previously/whether they had adapters.and we can have a race to see who finds the answer first.
    #promechaniclife

  11. #11
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    160. Not changing. I spent hours researching. That is why I turned to this forum. Wise guy.

  12. #12
    'brifter' is f'ing stupid
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    This should work, right? 160mm post mount frame > flat mount calipers w/ 160mm rotors?

    https://www.assolutions.ca/shop/adap...ith-160-rotor/
    #promechaniclife

  13. #13
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    I already ruled that out due to not enough clearance from top of post to fork/stay. However I did just get confirmation That
    Shimano BR-RS785 Post mount calipers are compatible. So there is one solution.

  14. #14
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    Welcome 1Robertpost! Consider Grumpy CXWrench's replies as your initiation to these forums. He's very knowledgeable and helpful, but gets really curmudgeony when he seen the word "brifter" or when people post in the sub forum section. Be glad you posted in the right sub forum!
    "COMPLACENCY IS LETHAL - VOTE in November." - System Shock.

    "With
    bicycles in particular, you need to separate between what's merely true and what's important."
    -- DCGriz, RBR.





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