Worth upgrading rear derailleur?

loz_the_guru
loz_the_guru Posts: 33
edited October 2019 in Workshop
Hi all,

I run 6800 on my 'nice' bike and 4700 on my commuter/winter bike. I've always found the 4700 sluggish/heavy, and have even wondered if there's some cable drag somewhere along the way as the leavers need to be pressed noticeably harder before anything moves.

I've been reading up on compatibility between groupsets, which is a particular nightmare as aI run a 50/34 at the front and a 11/32 at the back. I had thought to change both the shifters and rear derailleur to a 6700 setup, keeping the 4700 at the front but it seems that even that can have issues.

I've seen various people commenting that 4700 shifters are unusual as they are compatible in a 10 speed set up with 5800/6800 rear derailleurs.

So, my question is - would I see a noticeable improvement by popping a 5800/6800 RD in place of my 4700? Or should I stick with my original plan and change both the shifter and the RD to a 6700?

Comments

  • johngti
    johngti Posts: 2,508
    I’ve just bought a new bike fitted with 4700 and was really impressed with it last weekend. Certainly didn’t get a draggy/heavy feeling. Time for new cables perhaps?
  • Thanks, good to hear that as it's very difficult without anything to compare it to! I bought the bike from Tredz and it's always felt like that - I wonder if it's something to do with how it was originally set up? I might take a look next weekend when my bar tape arrives.
  • First.Aspect
    First.Aspect Posts: 14,498
    You aren't going to feel any difference with another RD. Either you have a long run of cable housing or the shifters are a bit vague. Or both.

    You might get a better feeling with new shifters, but new cables and outers are a cheap test first. Or do what I do and just flush the outers with wd40 before fitting new cables. I'm a bit lazy, really.
  • pinno
    pinno Posts: 51,199
    Thanks, good to hear that as it's very difficult without anything to compare it to! I bought the bike from Tredz and it's always felt like that - I wonder if it's something to do with how it was originally set up? I might take a look next weekend when my bar tape arrives.

    Clean it all up, lubricate the levers and check:

    Frayed inner cable
    Wear around the BB cable guide
    Badly cut outer cables that obfuscate the inner cable movement - this could be the concealed part of the outer that slots into the levers
    Look for excessive cable between the seat stay and the rear mech
    Whilst you are there, check for ease of cable movement where the cable goes int the rear mech and also through the nipple on the chainstay
    Remove the cable from the rear mech and see if the levers click nicely and freely
    Make sure the outer cables are firm into the gear levers. Unfortunately, this will often mean removal of handlebar tape

    Have a read of this:

    viewtopic.php?f=40004&t=13084278
    seanoconn - gruagach craic!
  • keef66
    keef66 Posts: 13,123
    Correct; 4700 uses the same cable pull as the 11 speed stuff. It won't work with older 10 speed.

    Unless the RD is completely seized, draggy shifting is much more likely to be cable related, and that's supported by the fact you say it's been like that from the off.

    I'd first treat it to a new set of cables, inners and outers, new end caps, ferrules etc. Be pathological about finishing the cut ends of the outers.
  • mugensi
    mugensi Posts: 559
    4700 is much nicer and slicker than 6700 which is 10 year old technology and not particularly good IME
  • timothyw
    timothyw Posts: 2,482
    Yeah, problem is the cables/poor factory setup.

    I suggest getting the proper shimano ones - https://www.wiggle.co.uk/shimano-105-58 ... cable-set/

    As above take care when setting up that you don't leave any pinch points that might drag the cable.
  • Ben6899
    Ben6899 Posts: 9,686
    What are the cable runs like? I'm considering changing out the internal routing bars on my Donhou. As nice as they are, the cable route is shite and can be felt.
    Ben

    Bikes: Donhou DSS4 Custom | Condor Italia RC | Gios Megalite | Dolan Preffisio | Giant Bowery '76
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