Chain line problem.....need advice- Mtbr.com
Results 1 to 8 of 8
  1. #1
    mtbr member
    Reputation:
    Join Date
    Oct 2005
    Posts
    20

    Upset Chain line problem.....need advice

    Soooo...I got the new boone chainwheel installed on the singleton. But the chainline is WHACKED! Its a good 4 or 5 millimeter "inside" the rear cog.

    Well, I can get the correct chainline, but I have to run my EBB mechanism "outside" of it's intended channels. In other words, there are groves that run around the diameter of the mechanism, that the set screws fall into when clamped. Well I can off set the mech to correct my chainline, but the set screws are no longer terminating in the groves. There is still plenty of mech to grab on to.....but they are NOT in the groves.

    Any thoughts? Do I need a spacer of some kind? This is pretty important, as I am going to Tyler on this sled MONDAY and I DO NOT WANT any failures.

    Bike - Zion w/ebb
    Mech - stock w/frame
    Cranks - XTR 952 w/proprietary interface
    Chainwheel - boone custome w/proprietary interface

    Thanks for the input. I can provide photos if needed.

    Ryan

  2. #2
    mtbr member
    Reputation:
    Join Date
    Dec 2003
    Posts
    3,662
    As the saying goes : A picture is worth a thousand words.
    A pic of the Crankset will do, from the side & the BB.

    - Whatever you do, DON'T slide the EBB side to side inside the BB shell.

  3. #3
    Nouveau Retrogrouch SuperModerator
    Reputation: shiggy's Avatar
    Join Date
    Dec 1998
    Posts
    48,236
    What hub are you using? Is there adjustment room on the rear?
    mtbtires.com
    The trouble with common sense is it is no longer common

  4. #4
    No Justice = No Peace
    Reputation: Lutarious's Avatar
    Join Date
    Feb 2005
    Posts
    1,512

    Hmmm....

    Sounds like you might need to space the chainring in on the cranks. Can you put a spacer behind it so the ring runs closer to centerline?
    "Welcome to my underground lair...."

  5. #5
    mtbr member
    Reputation:
    Join Date
    Oct 2005
    Posts
    20

    Pics for perspective...


    XTR 952 with Boone ti chainwheel



    Non-drive side. As you can see there is about 3-4 mm in from the edge of the BB shell.




    Drive side. On this side the mech is flush with the BB shell.

    So before I installed the boone chain wheel, the mech was perfectly centered w/1.5 to 2 mm on each side of the mech before the edge of the BB shell. Now I have moved the mech off center 3-4mm in order to accomidate the chain line issue.

    The mech is NOT pertruding out of the BB shell. It is flush. However, the set screws are NOT in the intended channels. (if this is bad, please explain why)

    Rear hub is a Paul SS disk hub. Free wheel is white industries. No adjustment available on the back side.

    Thanks for looking.

    Ryan
    Last edited by flee; 12-23-2005 at 09:26 PM.

  6. #6
    mtbr member
    Reputation:
    Join Date
    Dec 2003
    Posts
    3,662

    Hmmm Flee

    I can't say that I've ever seen an EBB that wasnt flush with the BB housing on both sides of the BB shell.
    If there are intended places for the set screws to do their thing against the EBB I'd do that.
    You can do a several things :
    - Number 1 (and probably the proper fix) is get a wider BB.
    - Number 2, you can put a spacer or two on the Drive-side. I think by going the spacer route you will then compromise the Non-Drive-side Crank/Chainstay spacing.
    - Number 3, buy a White Ind. ENO Hub, they carry the Freewheel 4 or 5 mm further inboard than Pauls, Phil Wood, etc.
    - Number 4, go with a Cassette hub for ease of adjustment, PLUS you'd get to buy a Boone Cog to match that SWEET Chainring!

    Good luck!

  7. #7
    mtbr member
    Reputation:
    Join Date
    Oct 2005
    Posts
    20

    Fixed!!!!

    Thanks for looking. I remembered that my 113 mm bottom bracket is off set. Turns out the longer side of the spindel was on the non-drive side. I went out, pulled off the arms and flipped the entire mech. The chainline is PERFECT and the mech is centered as it was before. Set screws now terminate in the channels.

    I'm good to GO!

    Thanks again.

  8. #8
    Nouveau Retrogrouch SuperModerator
    Reputation: shiggy's Avatar
    Join Date
    Dec 1998
    Posts
    48,236
    Quote Originally Posted by flee
    Thanks for looking. I remembered that my 113 mm bottom bracket is off set. Turns out the longer side of the spindel was on the non-drive side. I went out, pulled off the arms and flipped the entire mech. The chainline is PERFECT and the mech is centered as it was before. Set screws now terminate in the channels.

    I'm good to GO!

    Thanks again.
    Be sure to check the tightness of the BB in the EBB insert often. You just reversed the threads and pedaling may loosen it.

    BTW I have never heard the EBB insert called a "mech" before. It is just a single hunk of machined aluminum with no moving parts. The Brits call derailleurs mechs.
    mtbtires.com
    The trouble with common sense is it is no longer common

Members who have read this thread: 0

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.