High gear clacking out

Discussion in 'Bicycle Repair' started by davidsis, Dec 5, 2007.

  1. davidsis

    davidsis Guest

    Every time I put my mountain bike in High gear my chain keeps popping off and slipping forward. Any ideas I have changed the spring in the derailer and it is still all jacked up.

  2. OldPete

    OldPete Guest

    If the chain is not worn and/or does not have frozen links it is prolly just a matter of adjusting the derailer(sp).

    www.parktool.com/repair/ click on the area of interest.
  3. JemmaUK

    JemmaUK Guest

    It does sound like the deraillier needs adjustment especially since you have changed the spring. The change will mean there is a different tension in the deraillier and therefore it will be the top & bottom ratios that will cause problems...

    good luck with it :)

    Jemma xx
  4. davidsis

    davidsis Guest

    High gear

    Thanks, the chain has already been checked, and the spring did not change a thing same problem exact. Jemma, you sure are mechanical for a Female.
  5. JemmaUK

    JemmaUK Guest

    Thank you :)

    I think the thing to check next is the trim screws to the back of the deraillier casing. One will trim top (wheel side of the cassette) and the other bottom (drop-out side of the cassette). Hopefully judicious adjustment should solve the problem..

    I like compliments... flattery will get you everywhere

    Jemma xx
  6. Egor

    Egor Guest

    Try this. The high gear is the small ring, if you look at it in that gear count the teeth the chain is using. If you put too much spring in the twist portion of the derailleur it will rock it back and take the chain off some of the teeth. It is a fine balance to get the adjustments correct. Have fun, Dave
    PS: If the edges of the teeth are rounded over nothing will fix it. You will have to get a new ring.
  7. davidsis

    davidsis Guest


    Thanks I guess I will get to work turning screws. Jemma I like your myspace page.
  8. OldPete

    OldPete Guest

    Use the Park Tool link I offered up above. ;)
  9. JemmaUK

    JemmaUK Guest

    Be gentle on your adjustments - too far and you'll never get the thing back working properly - I did that the first time I tried it and I could never get the indexing back on that bike however I tried..The best way is put the bike upside down and slowly pedal the bike... you'll be able to eyeball the adjustments that way..

    Thanks for the page comment - I havent put anything up on there for ages.. alot of things going on lol..

    Jemma xx
  10. OldPete

    OldPete Guest

    It is best to do the shifting adjustments with the bike right side up. Up side down will get it close but not on the money. Before I bought a bike service stand I would suspend the rear wheel from a rope over a garage rafter, then do the adjustment never turning more than an 1/8 turn at a time.
  11. OldPete

    OldPete Guest

    Is the shifting sorted out?
    Last edited by a moderator: Dec 9, 2007