Dura Ace hydro brake failure- Mtbr.com
Results 1 to 12 of 12
  1. #1
    mtbr member
    Reputation:
    Join Date
    Apr 2018
    Posts
    365

    Dura Ace hydro brake failure

    ST-9120-R. Early 2018 build.

    just torquing these down like i've done with shimano hydros two dozen times and they crack WELL below max torque and WELL before the nuts were close to bottoming out on the housing.

    super disappointed and has made me consider switching to sram.

    Dura Ace hydro brake failure-20190226_124218.jpg

    Dura Ace hydro brake failure-20190226_132526.jpg
    Attached Thumbnails Attached Thumbnails Dura Ace hydro brake failure-20190226_124214.jpg  


  2. #2
    was fast
    Reputation:
    Join Date
    Jan 2011
    Posts
    42
    Something to verify when tightening that compression nut: be sure to keep a small amount of preload on the hose its bottomed in the housing. I have 3 bikes with ST-R9170 (Di2 hydro) that use the same compression nut. None of them bottom completely. Typically about 1~2 threads still showing on nut. Many thousands of miles, gravel, CX, road (and a national championship) on them and no cracks.

    Issue I did have was the internals becoming clogged so the lever would not draw fluid from the reservoir. Shimano warranteed two L levers for me.

  3. #3
    mtbr member
    Reputation:
    Join Date
    Oct 2018
    Posts
    812
    So you've done it 24 times, and after one failure you're considering a brand switch?

  4. #4
    Ride Fast Take Chances :)
    Reputation: alexbn921's Avatar
    Join Date
    Mar 2009
    Posts
    2,849
    You keep spamming this. Get over it man.
    Making shit harder than it needs to be isn't awesome, it's just...harder.

  5. #5
    mtbr member
    Reputation:
    Join Date
    Apr 2018
    Posts
    365
    Quote Originally Posted by Emilio700 View Post
    Something to verify when tightening that compression nut: be sure to keep a small amount of preload on the hose its bottomed in the housing. I have 3 bikes with ST-R9170 (Di2 hydro) that use the same compression nut. None of them bottom completely. Typically about 1~2 threads still showing on nut. Many thousands of miles, gravel, CX, road (and a national championship) on them and no cracks.

    Issue I did have was the internals becoming clogged so the lever would not draw fluid from the reservoir. Shimano warranteed two L levers for me.
    thanks for the tips. ill leave a several threads showing.

  6. #6
    mtbr member
    Reputation:
    Join Date
    Apr 2018
    Posts
    365
    [QUOTE=alexbn921;14004914]You keep spamming this. Get over it man.[/QUOTEt

    trggrd. send me $500 and i will.

  7. #7
    mtbr member
    Reputation:
    Join Date
    Apr 2018
    Posts
    365
    Quote Originally Posted by Forest Rider View Post
    So you've done it 24 times, and after one failure you're considering a brand switch?
    nah it's the other issues cropping up lately. eg mtb disc bite point issue. chainring QA prob. 9100 anodization probs, 9100 pedal seals,

  8. #8
    mtbr member
    Reputation:
    Join Date
    Nov 2004
    Posts
    3,045
    I have 2 sets that I had to change the lines around because I run the rear brake moto style on the left.
    Zero issues.
    You should probably change to SRAM.

  9. #9
    mtbr member
    Reputation:
    Join Date
    Apr 2018
    Posts
    365
    Quote Originally Posted by the mayor View Post
    I have 2 sets that I had to change the lines around because I run the rear brake moto style on the left.
    Zero issues.
    You should probably change to SRAM.
    IDK. It's heading that way for sure. shimano unsurprisingly declined warranty claim. some fault on my end, i guess, but still a design flaw IMO. between that and the other issues, they're losing ground.

    sram 1x AXS 12-speed wireless with hope calipers is looking pretty good...if the batteries are staying put and the M/C pistons aren't swelling up anymore.

    cant win...

  10. #10
    mtbr member
    Reputation: DethWshBkr's Avatar
    Join Date
    Nov 2010
    Posts
    2,198
    Proper torque is keep cranking till it snaps, then back off 1/4 turn.






    That really does stink though. I recently did a set of Ultegra Di2 hydros. I had a definite resistance from the compression olive.
    On something like that, I personally wouldn't torque it, but go by feel. Those things are pretty stout right there.....

  11. #11
    mtbr member
    Reputation:
    Join Date
    Apr 2018
    Posts
    365
    Quote Originally Posted by DethWshBkr View Post
    Proper torque is keep cranking till it snaps, then back off 1/4 turn.






    That really does stink though. I recently did a set of Ultegra Di2 hydros. I had a definite resistance from the compression olive.
    On something like that, I personally wouldn't torque it, but go by feel. Those things are pretty stout right there.....
    haha.


    i thought i was going by feel - i'm usually pretty close when i check myself. o well. lesson learned.

  12. #12
    mtbr member
    Reputation:
    Join Date
    Nov 2004
    Posts
    3,045
    Quote Originally Posted by DethWshBkr View Post
    Proper torque is keep cranking till it snaps, then back off 1/4 turn.
    That's terrible advice. You should always crank until sparks and smoke come out of the threads and then stop. Then spray it all with WD40.

Similar Threads

  1. Dura Ace rear 7900
    By red5jedi in forum Weight Weenies
    Replies: 7
    Last Post: 09-06-2011, 04:23 PM
  2. Dura Ace Rear Cassette - Help
    By jacobslide in forum Drivetrain - shifters, derailleurs, cranks
    Replies: 7
    Last Post: 02-05-2011, 07:00 PM
  3. Dura Ace 7900 front derailleur with Shimano triggers
    By Danne in forum Weight Weenies
    Replies: 9
    Last Post: 01-28-2011, 08:21 AM
  4. Can I just throw Dura Ace STI brake/shift on my XTR?
    By superdosser in forum 29er Bikes
    Replies: 18
    Last Post: 07-12-2006, 02:26 PM

Members who have read this thread: 59

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  

THE SITE

ABOUT MTBR

VISIT US AT

© Copyright 2019 VerticalScope Inc. All rights reserved.