Rear Mech not taking up chain slack

samg123
samg123 Posts: 275
edited March 2013 in Workshop
Have an issue with my rear mech not taking up the chain slack, to the extent that the chain jumps off the cassette cause it's not fed on properly. The issue is the arm not springing back as it should- is there any way to fix this or is the mech buggered?

Comments

  • desweller
    desweller Posts: 5,175
    It depends on how patient you are.

    I fixed mine by wiggling it around in clean warm engine oil for a few minutes. Which doesn't sound too difficult, unless the only way you have of warming engine oil is on the stove in a saucepan. From which it follows that some concealment from SWMBO of this abuse of cooking utensils must take place. This is where some patience (and possibly a diversion) might be needed.

    On the plus side it has not seized up again since I did it, two winters ago, so it must have worked!
    - - - - - - - - - -
    On Strava.{/url}
  • samg123
    samg123 Posts: 275
    I live in a student flat with 4 other people- any suggestions on how I should explain this use of saucepans to them?!?
  • smidsy
    smidsy Posts: 5,273
    Do they even know they have saucepans?
    Yellow is the new Black.
  • samg123
    samg123 Posts: 275
    Of course- how else would we cook the pasta that forms 70% of our diet?
  • ratsbeyfus
    ratsbeyfus Posts: 2,841
    samg123 wrote:
    I live in a student flat with 4 other people- any suggestions on how I should explain this use of saucepans to them?!?

    Would chips deep fry in engine oil? Tell 'em that it's a Heston recipe.

    I had one of them red bikes but I don't any more. Sad face.

    @ratsbey
  • keef66
    keef66 Posts: 13,123
    Just shallow fry the mech with a couple of garlic cloves in some extra virgin olive oil.
  • sungod
    sungod Posts: 17,541
    samg123 wrote:
    I live in a student flat with 4 other people- any suggestions on how I should explain this use of saucepans to them?!?

    from my (distant) memory of student flats, no one would even notice :-)

    put the chain on small-small so there's loads of slack

    then manually move the rd arm back/forth through it's full range of movement a few times, if the bearing is simply bunged up, you should still be able to feel the spring resistance, if there's no resistance then the spring may have broken

    if it's just the bearing, take the rd off (if the chain has no quicklink, undo the rear cage so you can remove the rd without breaking the chain), strip it, clean it, lube it, reassemble

    exact method will vary according to make/model, if it's shimano you'll find exploded view diagrams here...

    http://techdocs.shimano.com

    ...for other makes look on the appropriate website
    my bike - faster than god's and twice as shiny
  • smidsy
    smidsy Posts: 5,273
    samg123 wrote:
    Of course- how else would we cook the pasta that forms 70% of our diet?

    Students....Cook.... 1st time that has ever come up in the same scentence.

    And as for your pasta, Has Pot Noodle ceased to exist :lol:
    Yellow is the new Black.
  • samg123
    samg123 Posts: 275
    Blasted it with half a can of JL-69: seems to have done the trick. High tech solutions!

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