Advertise on Bikeforums.net



User Tag List

Results 1 to 4 of 4
  1. #1
    Senior Member loty's Avatar
    Join Date
    Jun 2010
    My Bikes
    Specialized Rockhopper, Trek 7100
    Posts
    70
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)

    Occasional gear jump

    Hi, I have 2009 Specialized Rockhopper basic model that I bought new few months ago and maybe put a little more than 300 miles on it so far. Here is the story - I installed clipless pedals last week and as I never before rode clipless I fell with the bike a few times when stopping because I couldn't get my feet unclipped in time - I guess it's a rite of passage. So anyway, after the last fall my rear deraileur started acting up. Every few minutes or so my gear would jump to a higher one and then jump back. I can't figure out exactly when it happens or what makes it happen - it happens intermittently every few, sometimes up to 5 minutes, sometimes when I push hard, sometimes when I barely push on pedals.

    Any ideas what might the problem be and how to fix it?
    du kom for seint na ma du drikka mest

  2. #2
    coprolite fietsbob's Avatar
    Join Date
    Jun 2010
    Location
    NW,Oregon Coast
    My Bikes
    7
    Posts
    39,957
    Mentioned
    27 Post(s)
    Tagged
    0 Thread(s)
    A Fall suggests you bent the RD mount on the frame, go to your LBS and have that checked.
    Index allignment tool required, bike shops have them.
    ramps on face of next larger cog will pick up the chain, your index click is not centered over the cog so needs adjustment,
    maybe just the a cable adjustment with that housing screw on the brake/shift lever and RD in itself.
    they are fussy about that dropout eye allignment, get that checked first.

    chain may have a tight , dry , link too ..
    Last edited by fietsbob; 07-21-10 at 08:46 AM.

  3. #3
    Some guy with a bike serra's Avatar
    Join Date
    Apr 2010
    Location
    California
    Posts
    276
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    It might be loose. I'm not sure how falling would loosen it, but check that it's secured to the frame properly. Lots of things cause gear jumps, but I can't think of any that don't happen constantly while your pedaling. Intermittently is just weird.

  4. #4
    Senior Member loty's Avatar
    Join Date
    Jun 2010
    My Bikes
    Specialized Rockhopper, Trek 7100
    Posts
    70
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Thanks guys. I found some good articles on rear derailleurs (sheldon brown and others) and will try to see what's going on with it tonight. If I still can't figure it out a trip to my LBS will be in order.
    du kom for seint na ma du drikka mest

Posting Permissions

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