Results 1 to 9 of 9
  1. #1
    Trail Tire TV on blogger
    Reputation: thomllama's Avatar
    Join Date
    Oct 2007
    Posts
    3,947

    Chain hitting pivot joint on Rockstar 29er

    so helping a friend build a rockstar 29er frame, went and installed the rear derailleur and when in the 11 or 12 tooth rings on the cassette the chain is hitting the pivot joint on the chai stay..

    I can back the B screw WAYYY out and almost get it clear but them it's too far out and the chain will skip... any ideas?
    Going to try and bring Trail Tire TV back. go take a look... http://trailtiretv.blogspot.com/

  2. #2
    Trail Tire TV on blogger
    Reputation: thomllama's Avatar
    Join Date
    Oct 2007
    Posts
    3,947
    images
    Attached Thumbnails Attached Thumbnails Chain hitting pivot joint on Rockstar 29er-hit1.jpg  

    Chain hitting pivot joint on Rockstar 29er-hit2.jpg  

    Going to try and bring Trail Tire TV back. go take a look... http://trailtiretv.blogspot.com/

  3. #3
    Nouveau Retrogrouch SuperModerator
    Reputation: shiggy's Avatar
    Join Date
    Dec 1998
    Posts
    48,014
    Quote Originally Posted by thomllama View Post
    so helping a friend build a rockstar 29er frame, went and installed the rear derailleur and when in the 11 or 12 tooth rings on the cassette the chain is hitting the pivot joint on the chai stay..

    I can back the B screw WAYYY out and almost get it clear but them it's too far out and the chain will skip... any ideas?
    What chainrings are you using/ which ring is the chain on in the pic?
    mtbtires.com
    The trouble with common sense is it is no longer common

  4. #4
    Trail Tire TV on blogger
    Reputation: thomllama's Avatar
    Join Date
    Oct 2007
    Posts
    3,947
    Quote Originally Posted by shiggy View Post
    What chainrings are you using/ which ring is the chain on in the pic?
    chain rings wont matter, but it's a XTR 960.. in the middle at the time but does it in all of them.. at the picture it's still 3 rings up the cassette.. (14 tooth?)

    alspo tried an X0 Derailluer and it was worse even
    Going to try and bring Trail Tire TV back. go take a look... http://trailtiretv.blogspot.com/

  5. #5
    mtbr member
    Reputation: craigstr's Avatar
    Join Date
    Sep 2003
    Posts
    4,321
    Long cage, medium cage, or short cage derailleur? Possibly you have too much chain? I have found that in the small chainring/small cog combo the chain will hit on the V2 even with the B tension set correctly but I never use that combo anyway.

  6. #6
    Trail Tire TV on blogger
    Reputation: thomllama's Avatar
    Join Date
    Oct 2007
    Posts
    3,947
    Quote Originally Posted by craigstr View Post
    Long cage, medium cage, or short cage derailleur? Possibly you have too much chain? I have found that in the small chainring/small cog combo the chain will hit on the V2 even with the B tension set correctly but I never use that combo anyway.
    again, doesn't matter, but it's a long cage... chain length, cage length, all that stuff has no bearing on the upper jockey wheel position, just the lower... but the chain is sized properly
    standard 11-34, 9 speed cassette, regular 22-32-42 triple crank rings.. nothing out of the ordinary here

    I always do all my initial setup with the front on the middle chain ring.. I wouldn't do Small-Small either..

    what I find really odd is if you look at the first image.. the chain is still up on the third ring, when down on the 11 or 12 it's literally behind the actual seat stay (the white part) I just can't see the chain NOT hitting it during normal use.. it's a really poor design from what I can see... The derailleur kinda sits up way higher in relation to the cassette/axle than any other bike I've ever seen.. even if I could get it to clear it seems that when on the smaller gears on the cassette there would only be 3-4 teeth engaging the chain. can see that snapping the chain or the teeth off the cassette...
    Last edited by thomllama; 10-20-2012 at 12:35 PM.
    Going to try and bring Trail Tire TV back. go take a look... http://trailtiretv.blogspot.com/

  7. #7
    mtbr member
    Reputation: craigstr's Avatar
    Join Date
    Sep 2003
    Posts
    4,321

    Just trying to help you out

    If the B tension screw is set incorrectly and the chain is too long then it could be a problem because I have had the issue on few different bikes. I think you can add some B tension and get it to work. Here are pics of the V2 in the small cog and large cog. In both pics the chain is on the big ring (39) of an XO 2x10 setup.
    Attached Thumbnails Attached Thumbnails Chain hitting pivot joint on Rockstar 29er-p1020944.jpg  

    Chain hitting pivot joint on Rockstar 29er-p1020945.jpg  


  8. #8
    mtbr member
    Reputation:
    Join Date
    Jan 2007
    Posts
    235
    Check your rear derailleur mounting to make sure the spring stop is resting on the derailleur mount tab. Also try loosing the rear derailleur mounting bolt and turn the derailleur counter clockways about a 1/4" and tighten the mounting bolt. I had this same trouble with a early intense 5.5 and this worked.

  9. #9
    Trail Tire TV on blogger
    Reputation: thomllama's Avatar
    Join Date
    Oct 2007
    Posts
    3,947
    Quote Originally Posted by doralswheels View Post
    Check your rear derailleur mounting to make sure the spring stop is resting on the derailleur mount tab. Also try loosing the rear derailleur mounting bolt and turn the derailleur counter clockways about a 1/4" and tighten the mounting bolt. I had this same trouble with a early intense 5.5 and this worked.
    that was the first thing I checked.. also made sure that the springs and such were all wound correctly. the X0 is brand spanking new so there's nothing there set wrong.. but I checked it

    Quote Originally Posted by craigstr View Post
    If the B tension screw is set incorrectly and the chain is too long then it could be a problem because I have had the issue on few different bikes. I think you can add some B tension and get it to work. Here are pics of the V2 in the small cog and large cog. In both pics the chain is on the big ring (39) of an XO 2x10 setup.
    ummm from the 2nd photo, the B screw is set tooo far off ... tooth to tooth should be 5-6mm from the jockey to the large ring of the cassette, and Sram's are pretty sensitive to B screw adj.

    He did take it home and finished the build with the B set just out like you're image, it's at 11MM tooth to tooth.. he says it rides/works OK, but honestly, not something I recommend as even the very slightest twist to the derailleur hanger and you could get chain in spokes when up on the grannie gear
    Going to try and bring Trail Tire TV back. go take a look... http://trailtiretv.blogspot.com/

Posting Permissions

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