bb height, chain falling off- Mtbr.com
Results 1 to 5 of 5
  1. #1
    mtbr member
    Reputation:
    Join Date
    Aug 2007
    Posts
    480

    bb height, chain falling off

    I have exactly four hours experience riding my new specialized rockhopper 29 ss, so bear with me. Today's first ride has me wondering 2 things:

    1) the chain fell off repeatedly. The bike uses a sliding rear dropout and I got the chain nice and tight and fiddled with the spacers in the back, but it pops off on bumps. I ordered an outer bash guard and chain watcher today, hopefully it's just the chain bouncing off.

    2) I bang my pedals all the time. I did not measure it yet, but the BB height seems like riding a road bike, even my cross bike seems to have better pedal clearance. Is the a 29er thing or just a specialized thing? It's kind of a pain, as when I whack the pedal the chain derails too.

    Other than that I like both the bigger wheels and the single speed aspect. I'm a little sore I must say.

  2. #2
    mtbr member
    Reputation:
    Join Date
    Aug 2009
    Posts
    7
    Quote Originally Posted by jroden
    I have exactly four hours experience riding my new specialized rockhopper 29 ss, so bear with me. Today's first ride has me wondering 2 things:

    1) the chain fell off repeatedly. The bike uses a sliding rear dropout and I got the chain nice and tight and fiddled with the spacers in the back, but it pops off on bumps. I ordered an outer bash guard and chain watcher today, hopefully it's just the chain bouncing off.
    Um....it's not supposed to come off. You don't need a bash guard or a chain watcher to keep it on, you just need proper chain tension. Take it to a mechanic and have them show you a proper method for getting it tight enough maybe?

    Quote Originally Posted by jroden
    2) I bang my pedals all the time. I did not measure it yet, but the BB height seems like riding a road bike, even my cross bike seems to have better pedal clearance. Is the a 29er thing or just a specialized thing? It's kind of a pain, as when I whack the pedal the chain derails too.
    Meh, it is what it is. You can always play with fork lengths if it bothers you too much.

  3. #3
    mtbr member
    Reputation:
    Join Date
    Aug 2007
    Posts
    480
    It has a sliding mechanism on the dropouts and I applied a lot of pressure with my hand and tightened it--am I missing something?

  4. #4
    My spoon is too big!
    Reputation: medieval's Avatar
    Join Date
    Oct 2007
    Posts
    881
    Check that the wheel and chainline are straight. Even a tight chain can derail, if something is crooked.
    "If more of us valued food and cheer and song above hoarded gold, it would be a merrier world."
    J. R. R. Tolkien

  5. #5
    Retro Grouch
    Reputation: aka brad's Avatar
    Join Date
    Dec 2003
    Posts
    2,091
    Quote Originally Posted by jroden
    It has a sliding mechanism on the dropouts and I applied a lot of pressure with my hand and tightened it--am I missing something?
    The Rockhopper 29er SS I have seen have an eccentric bottom.


    edit; okay my bad, I found this pic of the "Expert". My guess is the dropouts are slipping; need to be cleaned and tightened with more torque
    Attached Thumbnails Attached Thumbnails bb height, chain falling off-rh.jpg  

    Last edited by aka brad; 05-15-2010 at 09:23 PM.
    Just one more rep and I get the toaster!

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.