rear mech/shifting adjustment woes

Uber_Pod
Uber_Pod Posts: 110
edited April 2018 in MTB workshop & tech
The main problem is having to shift once *and a bit* most times. Or shift twice and back one to get to where I want.
No obvious difference with high or low gears and seems to happen shifting up and down.

A new (admittedly second hand) shifter and cable has made no difference. (the XT shifter feels much nicer though!)
I've tried turning the adjuster on the shifter but can't get it right.

I'm sure it's an adjustment issue, I'm just not sure which bit.

The quick answer would be take it to a bike shop, but I want to learn what I'm doing wrong and ideally how to do it right.
Is it just a case of re-reading the various online instructions again, or is there an obvious specific part to look at first?

Comments

  • cooldad
    cooldad Posts: 32,599
    Go to the Park Tools link below.
    I don't do smileys.

    There is no secret ingredient - Kung Fu Panda

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  • swod1
    swod1 Posts: 1,639
    GMBN on youtube have a video of gear indexing. its not hard before tightening the pinch bolt on the rear derailleur wind the barrel adjuster on the shifter all way in and then back off a couple of turns only.

    Then pull the gear cable to take out the slack but not too much as you'll move over the rear mech on to the next gear and then do up the pinch bolt to secure the cable. The gears should change up and down without any fiddling with the barrell adjuster on the shifter.

    Make sure when you do this the chain is on the highest gear (smallest cog) on the cassette.
  • What about chain and cassette wear?

    Could be worn out rear mech as well.
  • cooldad
    cooldad Posts: 32,599
    swod1 wrote:
    GMBN on youtube have a video of gear indexing. its not hard before tightening the pinch bolt on the rear derailleur wind the barrel adjuster on the shifter all way in and then back off a couple of turns only.

    Then pull the gear cable to take out the slack but not too much as you'll move over the rear mech on to the next gear and then do up the pinch bolt to secure the cable. The gears should change up and down without any fiddling with the barrell adjuster on the shifter.

    Make sure when you do this the chain is on the highest gear (smallest cog) on the cassette.

    Assuming the limit screws are correctly adjusted, which is the first step.
    I don't do smileys.

    There is no secret ingredient - Kung Fu Panda

    London Calling on Facebook

    Parktools
  • 02gf74
    02gf74 Posts: 1,171
    Need more info.
    Has it always done this or started recently, if latter, what was changed

    Are shifter, mech, chain and cassette compatible?
  • Uber_Pod
    Uber_Pod Posts: 110
    Thanks for the suggestions. I'll have another go at adjusting it this weekend, using the parktools guide to start with.

    It's pretty much always done it since I started fiddling with it. Not sure I'll ever learn that lesson.
    Parts are definitely compatible. Everything is now 9 speed XT.
  • cooldad
    cooldad Posts: 32,599
    Just loosen everything off, start from scratch, and do it step by step.
    I don't do smileys.

    There is no secret ingredient - Kung Fu Panda

    London Calling on Facebook

    Parktools
  • Uber_Pod
    Uber_Pod Posts: 110
    Well, I had another go and it's much better. Still not quite right, but I'll get there.
  • photonic69
    photonic69 Posts: 2,836
    Could be a bent hanger? Mine was like this until I got a HAG (Hanger Alignment Gauge). Now shifting is a joy!


    Sometimes. Maybe. Possibly.

  • swod1
    swod1 Posts: 1,639
    If the mech hanger is bent you can straighten it back with a big adjustable spanner but be careful as you can snap them off.