Forum home Road cycling forum Workshop

Dreadful rear mech shifting.

willhubwillhub Posts: 821
edited March 2015 in Workshop
Hi.

I'm at a loss how to solve this, no matter how much I tend to cable tension or faff with the H/L screws, the shifting is horribe, I have to click twice up and once down to get up a sprocket, shifting down with a simple one downshift seems to work.

The rear mech in question is a Shimano 105 9/10 Speed 5700 on a 10 speed Tiagara, I've just replaced the rear mech with an exact duplicate (brand new as placing the old rear mech on my carrera).

Now the old 5700 off of my Planet X has gone onto the Carrera, banged it on and with 9 speed chain and front shifters (Tiagra again but shifters like 10 years old).

On the Carrera the shifting is perfect with little messing about, but the Planet X just won't have it.

Why is shifting so dreadful I don't know what else can be adjusted ?!?!

Posts

  • crikeycrikey Posts: 362
    The rear mech in question is a Shimano 105 9/10 Speed

    It's either a 9 speed mech or a 10 speed mech, that may well be the issue.
  • willhubwillhub Posts: 821
    No it's a 9/10 speed mech.

    Shimano Rear mech that is 10 speed works on 9 speed.

    So as I mentioned above where I say the mech (which is listed as 10 speed) works perfectly on the Carrera (9 speed), yet both mechs (both of which being on the Planet x and are "10 speed" as well as the full drivetrain on the Planet X being 10 speed) shift like censored on the Planet X.
  • crikeycrikey Posts: 362
    Ok, you know best... Happy shifting....
  • willhubwillhub Posts: 821
    crikey wrote:
    Ok, you know best... Happy shifting....

    Clearly, you're telling me it does not work because it's meant for 10 speed.

    I'm telling you it's on a 10 speed bike but clearly you can't read, numpty.
  • Smokin JoeSmokin Joe Posts: 2,706
    9 and ten speed mechs are the same as the OP states, so that won't be the problem. Try new cables first or the shifters may be faulty.
  • arlowoodarlowood Posts: 2,527
    Smokin Joe wrote:
    9 and ten speed mechs are the same as the OP states, so that won't be the problem. Try new cables first or the shifters may be faulty.


    +1 If the mech works fine on the Carrera but not on the Planet X then the 2 variables are cables and shifters. I would strip down and inspect the cables for frayed areas etc. Also give them a good clean and lubricate with some Teflon spray or similar. Might also be a cable routing issue that's causing the problem.

    Also you may be exacerbating the problem by faffing about with the limit screwss. They have nothing to do with indexing - they only define how far the mech can move.

    For one of the more definitive guides to indexing have a look at this

    https://www.youtube.com/watch?v=SkzvfCaIbyQ
  • crikeycrikey Posts: 362
    I'm telling you it's on a 10 speed bike but clearly you can't read, numpty.

    But I can put bike bits together that work.... :lol:
  • frisbeefrisbee Posts: 691
    Bent hanger can affect shifting.
  • ror3hror3h Posts: 68
    Yep most likely a bent derailleur hanger. 2 min job with the correct tool.
  • trailflowtrailflow Posts: 1,311
    If the hanger is not bent,check it is secured to the frame properly.

    Try lubing the shifter internals mechanism.

    Check there are no burrs on the cable outer ends or ferrules.

    Make sure the cable is clamped in the correct place.


    Dont pull the cable too tight when clamping. Try to avoid 'wind up' on the cable so the RD doesn't rise slightly when clamping the bolt. Use the RD barrel adjuster to fine tune the cable tension.

    Check the cassette lock ring is tight.

    Check the rear wheel is seated in the drop outs properly.

    Check for stiff links.

    Check the jockey wheels bolts are tight.
Sign In or Register to comment.