Cleaning: Should I dismantle my shifter?

davis
davis Posts: 2,506
edited March 2010 in The workshop
I've got a sticking "bigger ring, please" lever on my Shimano R440 thumb shifter. I've changed the complete cable, and sprayed GT85 in the bits that slide. I've blasted more GT85 through the shifter, but the lever still sticks (it won't return to the neutral position without my pushing it back).

Should I take the shifter apart? I'm somewhat leery of a massive explosion of tiny tiny springs, screws, doodads and thingummys.

I'm thinking of taking the black underside cover off, by undoing the screws marked "A", "B", and "C" in this photo

I believe the screw marked "D" is a bit of a red herring.

Should I do this? Will I be furtling around under the freezer for some vital component at 11pm if I try it?
I've tried googling for specific instructions for this, but to no avail.

Edit: Just to be clear: it's not the cable. It's happening even with no cable installed
Sometimes parts break. Sometimes you crash. Sometimes it’s your fault.

Comments

  • davis
    davis Posts: 2,506
    Well, I've sorted it (or at least I know what the problem is). It's safe to remove all the screws shown.
    The screw labelled "D" did indeed secure the little cover over the central part of the shifter. A bit of poking about with it removed from the bike showed that the black plastic outer was deformed, and the small circular central cover was rubbing against it, stopping the lever returning. Lubricating the contact surface between these two pieces with Vaseline allowed it to move more freely and return.

    Now to replace the damn bar grips.
    Sometimes parts break. Sometimes you crash. Sometimes it’s your fault.
  • davis
    davis Posts: 2,506
    Sorted. Yay.

    It now shifts beautifully. Next job is to replace the cassette and chain.
    Sometimes parts break. Sometimes you crash. Sometimes it’s your fault.
  • supersonic
    supersonic Posts: 82,708
    Vaseline? This can dry out - I would use some teflon grease.

    It is very rare I take my shifters apart.
    GT ZASKAR CARBON TEAM

    VOODOO CANZO

    Come and see me at https://www.facebook.com/biketyke/
  • davis
    davis Posts: 2,506
    supersonic wrote:
    Vaseline? This can dry out - I would use some teflon grease.

    It is very rare I take my shifters apart.

    Hmmm.... Ok, thanks for that. I'll keep an eye on it and just hope it'll be ok. On the other hand, these shifters have done 18 months with no tweaking whatsoever, and a new LH shifter is £12 from CRC.
    Sometimes parts break. Sometimes you crash. Sometimes it’s your fault.
  • supersonic
    supersonic Posts: 82,708
    Mine have done 13 years and nothing but a squirt of lube inside with a straw!
    GT ZASKAR CARBON TEAM

    VOODOO CANZO

    Come and see me at https://www.facebook.com/biketyke/
  • cjcp
    cjcp Posts: 13,345
    +1 for teflon grease. There is no way I'd take my shifters apart. Haven't done it for 8 years and not about to start now :) .
    FCN 2-4.

    "What happens when the hammer goes down, kids?"
    "It stays down, Daddy."
    "Exactly."
  • davis
    davis Posts: 2,506
    Ah, cool sounds like I should get some more use out of these then! I've got a feeling that I rested the shifter on another bike's bars for a long time, which probably deformed the shifter housing.

    Right, I'll stop waffling and get to bed.

    Thanks for the advice, by the way
    Sometimes parts break. Sometimes you crash. Sometimes it’s your fault.

Categories