Breaking Carbon Brakes?- Mtbr.com
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  1. #1
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    Breaking Carbon Brakes?

    I did a very low speed endo, light impact. But I snapped off most of the lever blade of my Juicy Carbon rear brake. (I would never have purchased such a luxury -won 'em in a raffle) The lever snapped like a matchstick with seemingly light force. I always wondered if they would survive a crash -so there's my answer. Aluminum replacement levers are on back order, and carbon is almost $60 EACH. Plus install (which I don't feel competent to perform). LBS says the brake will need to be bled which adds to the install $$$. Ouch!

    I also brake a carbon seatpost, but that was long ago. Makes me wary of Carbon components, frames, etc. in general -esp. carbon bars.

    Anybody w/similar breakage? Any informed opinions?
    I like to bike.

  2. #2
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    Carbon is not designed with impact resistance in mind. I use carbon bars all the time, but if they were to take a dent, I would throw them away.

  3. #3
    Spice
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    I think parts like the lever blade havnt really been designed with strength in mind, but mainly ergonomics.
    I dont trust the carbon levers on my CR's to be honest :\

  4. #4
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    Next time leave your brake lever and shifter clamps slightly loose so that the lever can rotate in a crash.

  5. #5
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    Quote Originally Posted by XSL_WiLL
    Next time leave your brake lever and shifter clamps slightly loose so that the lever can rotate in a crash.
    +1

  6. #6
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    Preventive measures

    I USED to remember to do that. But I think this was a head-on impact, not sure if rotation would have helped. I will loosen both sides for the future -thanks.

    Quote Originally Posted by XSL_WiLL
    Next time leave your brake lever and shifter clamps slightly loose so that the lever can rotate in a crash.
    I like to bike.

  7. #7
    Meh.
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    Well, levers are typically angled. So a head on collision would probably still push the levers and cause them to want to rotate.

  8. #8
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    Quote Originally Posted by Fairfaxian
    I did a very low speed endo, light impact. But I snapped off most of the lever blade of my Juicy Carbon rear brake. (I would never have purchased such a luxury -won 'em in a raffle) The lever snapped like a matchstick with seemingly light force. I always wondered if they would survive a crash -so there's my answer. Aluminum replacement levers are on back order, and carbon is almost $60 EACH. Plus install (which I don't feel competent to perform). LBS says the brake will need to be bled which adds to the install $$$. Ouch!

    I also brake a carbon seatpost, but that was long ago. Makes me wary of Carbon components, frames, etc. in general -esp. carbon bars.

    Anybody w/similar breakage? Any informed opinions?
    Erm... lever removal and install is REAAAALLLYYY easy... and if the brakes were working fine before, they shouldn't need to be bled... sounds like the LBS is trying to make a quick buck off of you.
    Quote Originally Posted by Dictatorsaurus
    The way I see it right now, if my bike is too heavy, then I'm too weak!

  9. #9
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    No bleed necessary. Shop may not know that. Many think that any sort of service requires a bleed.

    You need to loosen a 3mm allen and unthread the 2.5mm pushrod. Then the pivot pin pushes out of the lever. The lever comes right out.

  10. #10
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    Quote Originally Posted by XSL_WiLL
    No bleed necessary. Shop may not know that. Many think that any sort of service requires a bleed.

    You need to loosen a 3mm allen and unthread the 2.5mm pushrod. Then the pivot pin pushes out of the lever. The lever comes right out.
    This is MUCH easier than it sounds, instructions are availible on the SRAM website
    Quote Originally Posted by Dictatorsaurus
    The way I see it right now, if my bike is too heavy, then I'm too weak!

  11. #11
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    Quote Originally Posted by AlexJK
    This is MUCH easier than it sounds, instructions are availible on the SRAM website
    That's all there is to it... You only have to touch the 3mm grub screw and the 2.5mm pushrod. Once the grub screw is loosened, the pivot pin pushes right out. And the lever comes out once you unthread the 2.5mm pushrod from the barrel.

  12. #12
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    Damn! Thanks for all the inside beta. Forewarned = forearmed.

    But my OTHER question remains unanswered - is carbon frameworthy? Seems a tad delicate on impact. when I retired my first Blur (Aluminum), it looked like it had seen combat, but was ready for more. With carbon, there's no visual cue to warn of failure. Suddenly it's game over.
    I like to bike.

  13. #13
    ride hard take risks
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    Quote Originally Posted by Fairfaxian
    Damn! Thanks for all the inside beta. Forewarned = forearmed.
    Go to Sunshine in Fairfax Tony & Martin know their shiate.
    Formotion Products
    http://www.formot

  14. #14
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    Sunshine is the ONLY shop I go to -for over 15 years (I don't even shop online). And let's not forget the Professor . . . "E".

    Quote Originally Posted by dogonfr
    Go to Sunshine in Fairfax Tony & Martin know their shiate.
    I like to bike.

  15. #15
    ride hard take risks
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    Quote Originally Posted by Fairfaxian
    Sunshine is the ONLY shop I go to -for over 15 years (I don't even shop online). And let's not forget the Professor . . . "E".
    Then you know they have some reason just ask why they feel the brakes need bleeding.
    Formotion Products
    http://www.formot

  16. #16
    Bicyclochondriac.
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    Quote Originally Posted by Fairfaxian
    Damn! Thanks for all the inside beta. Forewarned = forearmed.

    But my OTHER question remains unanswered - is carbon frameworthy? Seems a tad delicate on impact. when I retired my first Blur (Aluminum), it looked like it had seen combat, but was ready for more. With carbon, there's no visual cue to warn of failure. Suddenly it's game over.
    I would not be so sure that an aluminum lever would not have been ruined as well. I can't speak for this particular application of CF, but in general it is stronger than AL if made right. So, yeah, I think it is certainly frame-worthy. Whether it is worth all the extra $ is another story.

  17. #17
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    Quote Originally Posted by kapusta
    I would not be so sure that an aluminum lever would not have been ruined as well. I can't speak for this particular application of CF, but in general it is stronger than AL if made right. So, yeah, I think it is certainly frame-worthy. Whether it is worth all the extra $ is another story.

    THE WEAKEST LINK!!!!!!!!!
    In a prang or crash, the weakest component is going to break. So by toughening up and external part such as the level, simply transmits the energy into the brake system and could easily seize a bolt or snap a pin, something internal and difficult to access or to change.

    Still not convinced which ones stronger in small applications such as a level, Carbon or Ally?!?!

  18. #18
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    Quote Originally Posted by 130tc
    Still not convinced which ones stronger in small applications such as a level, Carbon or Ally?!?!
    There is no blanket answer to that statement. Either can be bombproof or fragile.

  19. #19
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    Quote Originally Posted by 130tc
    THE WEAKEST LINK!!!!!!!!!
    In a prang or crash, the weakest component is going to break. So by toughening up and external part such as the level, simply transmits the energy into the brake system and could easily seize a bolt or snap a pin, something internal and difficult to access or to change.

    Still not convinced which ones stronger in small applications such as a level, Carbon or Ally?!?!
    Avids do have the pop-out/breakaway lever in order to help prevent or isolate damage to the internals. Usually levers are designed to "fail"... aluminum levers have sort of a bend zone.

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