loosening up a 105 RD

chatlow
chatlow Posts: 845
edited July 2017 in Workshop
Hey I am finding that my right shifter is feeling pretty tight going up the gears. Cable got replaced today and is definitely fine plus the shifter is loose when cable detached so was wondering what parts I can lube or grease up on the RD to help ease it?

Thanks

Comments

  • k-dog
    k-dog Posts: 1,652
    Did you change the outer too? That little loop after the chainstay gets stiff after a while and replacing at least that makes a significant difference.
    I'm left handed, if that matters.
  • chatlow
    chatlow Posts: 845
    k-dog wrote:
    Did you change the outer too? That little loop after the chainstay gets stiff after a while and replacing at least that makes a significant difference.

    i thought this too.. and was going to.. until I detached the cable from the RD and found that the shifters had hardly any resistance when holding the cable and going up the gears. It looks to be that the RD is getting old and needs some TLC but Im struggling to find anything to lube/grease other than the main spring which wont help really
  • freezing77
    freezing77 Posts: 731
    You need to lubricate the pivots, use something like GT85 and work the derailleur up and down the block. Easiest to do this by disconnecting the cable and moving the derailleur manually whilst turning the cranks. Not easy if you do not have a stand or similar, I hang mine from the gazebo.
    https://www.youtube.com/watch?v=hHK9DSxIPM0
  • 964cup
    964cup Posts: 1,362
    Better to take the derailleur off the bike, give it a good clean and then soak all the pivots in GT85 or PlusGas. That way you can work each pivot by hand through the full range of motion. Once it's freed up, degrease it and relube the pivots more sparingly, then refit. Just did this to a friend's completely seized Ultegra RD, which is now working well.
  • Alex99
    Alex99 Posts: 1,407
    You can check if the derailleur mechanism is stiff by hand. If it is, it's easy enough to do a full service if you're so inclined. The two main pivots (one where it attaches to the frame, and the other that tensions the chain) come apart by removing a c-clip and a recessed allen bolt respectively. The reason I suggest disassembling these first, it that they should be greased and there is no way to grease them unless you take them apart.

    Then I would work the work the shifting mechanism whilst submerged in e.g. white spirit. Of course, only worth doing if it IS stiff or you just like taking stuff apart.
  • k-dog
    k-dog Posts: 1,652
    I read what you said as you'd disconnected the cables and it moved freely - not the shifters.

    So, freezing77 is right - it needs a good clean and the pivots lubed. There's not a lot to the mechanism but it can take a good soak to get rid of the built up grittiness. I bought a bike for my son last year with derailleurs that I couldn't move at all but with a good soak in oil then a thorough clean have been as good as new.
    I'm left handed, if that matters.
  • svetty
    svetty Posts: 1,904
    Alex99 wrote:
    You can check if the derailleur mechanism is stiff by hand. If it is, it's easy enough to do a full service if you're so inclined. The two main pivots (one where it attaches to the frame, and the other that tensions the chain) come apart by removing a c-clip and a recessed allen bolt respectively. The reason I suggest disassembling these first, it that they should be greased and there is no way to grease them unless you take them apart.

    Then I would work the work the shifting mechanism whilst submerged in e.g. white spirit. Of course, only worth doing if it IS stiff or you just like taking stuff apart.

    ^ this
    FFS! Harden up and grow a pair :D
  • chatlow
    chatlow Posts: 845
    thanks all - i will give this a go tonight tomorrow. may as well due a full service of it . Appreciate the input
  • chatlow
    chatlow Posts: 845
    cleaned up the RD and also replaced the outer cable leading to it. Still 'heavier' than normal to change gear. RD seems smooth enough. Bit lost here. Is there a way to adjust the spring tension on a 105 RD?

    thanks
  • buckmulligan
    buckmulligan Posts: 1,031
    You don't mention which bike it's on, but does it have external cabling and a plastic cable guide underneath the BB like this:

    P1000423.jpg

    If so, I'd try greasing this. I've found it can work wonders in reducing cable friction, especially if it's an old setup and the cables have worn a deeper groove into the plastic guide.

    I usually just cover each of those slots with a thick grease like Park Tools Polylube, shift the front and rear derailleurs down (without turning the cranks) to release a bit of cable tension and try to mash it under the cables as best as possible.
  • step83
    step83 Posts: 4,170
    Spring is a set tension so nothing you can do there, Id still be inclined to change the change the outers if possible depending on the frame you may get lucky an just need to do the RD loop.
    Titanium Px Spitfire
    Easty commuter
    Tripster AT
  • crankycrank
    crankycrank Posts: 1,830
    Step83 wrote:
    Id still be inclined to change the change the outers if possible depending on the frame you may get lucky an just need to do the RD loop.
    This. At least worth checking out. Cable movement can feel fine while detached from the mech but the outers may have some damage causing drag that only shows up under tension.
  • chatlow
    chatlow Posts: 845
    thanks will check out the plastic guide later on. I have replaced the outer cable going onto the RD as looked a bit old but the outer cable going to shifter looks okay.Could always change that too.

    I did notice that the 105 5700 shifter had 2 'channels' for the outer cables to slot into - 1 for the brake, then 2 next to each other for the gear cable. Is this just purely for positioning of the cable?

    thanks again all
  • crankycrank
    crankycrank Posts: 1,830
    chatlow wrote:
    1 for the brake, then 2 next to each other for the gear cable. Is this just purely for positioning of the cable?
    Yes, let's you choose the best routing for your setup.
  • chatlow
    chatlow Posts: 845
    not sure if cleaning the RD, greasing the guide or replacing the outer but it all seems to be a bit better now. Not perfect like it was but im happy and ready for sportive on the weekend :-D

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