Stiff front mech

gubber12345
gubber12345 Posts: 493
edited July 2017 in Workshop
The front mech on my road bike is very stiff to change up into the big ring.I've replaced the inner and outer cables and still it's the same if not worse now...any ideas as what's causing this or do I maybe need a new front deurailleur.
TIA
Lapierre Aircode 300
Merida

Comments

  • sungod
    sungod Posts: 17,340
    have you cleaned and lubricated it?
    my bike - faster than god's and twice as shiny
  • k-dog
    k-dog Posts: 1,652
    Probably just gummed up. Take it off and soak it for a couple of days (engine oil has worked for me in the past) and then move it by hand and it should free up.
    I'm left handed, if that matters.
  • gubber12345
    gubber12345 Posts: 493
    sungod wrote:
    have you cleaned and lubricated it?
    Yeah all cleaned up and oiled regularly...kind of got an ocd for it lol
    Lapierre Aircode 300
    Merida
  • gubber12345
    gubber12345 Posts: 493
    k-dog wrote:
    Probably just gummed up. Take it off and soak it for a couple of days (engine oil has worked for me in the past) and then move it by hand and it should free up.
    Felt pretty free when I had the cable off when renewing them but could maybe try your idea to see what happens.
    Lapierre Aircode 300
    Merida
  • k-dog
    k-dog Posts: 1,652
    If it's moving with no cable then it's probably fine.

    What's the mech/shifters? Could just be setup.

    If it's a Shimano double I've seen a lot of those where the trim position was being used to put it on the big ring - which makes it very stiff. I think that caused a lot of the broken shifters that were common 10 years ago.
    I'm left handed, if that matters.
  • gubber12345
    gubber12345 Posts: 493
    k-dog wrote:
    If it's moving with no cable then it's probably fine.

    What's the mech/shifters? Could just be setup.

    If it's a Shimano double I've seen a lot of those where the trim position was being used to put it on the big ring - which makes it very stiff. I think that caused a lot of the broken shifters that were common 10 years ago.
    Mech and shifter feel fine....could be setup but I've pulled it tight as I can to get it to work even.I've set the lower limit to about 1 mm from the mech.

    How would I know if it's on the trim function....i just pushed the lever til it was on the lowest setting to go on the small ring again.
    Lapierre Aircode 300
    Merida
  • k-dog
    k-dog Posts: 1,652
    You need to disconnect the cable, click the small lever a few times and then reconnect - it just needs a little tension at that time.

    I would start from scratch - if your limit screws are a little off then that means you really have to force the lever for it to catch the pawl. Here's my method - best I've ever had with Shimano 5600, no trim needed for the big ring and a really easy shift onto it.

    Start over. Undo the cable.

    When clamping the front derailleur to the frame make sure the gap between the big chainring teeth and front derailleur cage is 2-5mm.

    So first, with the cable de-attached. Put the chain on the small front ring and biggest back cog. Make sure to click the downshift lever into its lowest postion.

    Adjust the inner limit screw (closest to the frame on the front derailleur) so the gap is 1mm from the chain to the inner side of the front derailleur.

    Wind out the outer limit screw so it doesn't interfere in the next stage.

    Clamp the cable (finger tight cable tension - not too much). Then shift the chain onto the 11t cog (or smallest) at the back, and shift the front onto the big ring. There should now be some chain rubbing on the cage if you spin the cranks.

    Then wind the inline barrel adjuster (adding more cable tension) until there is a 1mm gap between the outer cage and chain, and no chain rub. Look down at the front derailleur cage as you do it.

    Then wind the outer limit screw in until it just touches the stop.

    Now shift the chain onto the small front ring, and the rear onto the second to last smallest cog. Then click into the front small ring trim position. Now whilst in the trim position - add more tension again with the barrel adjuster until there is no rub. Leave a gap of 2mm from the chain and the outer cage. This will eliminate any slop in the trim position and make it feel more positive.

    Check all gears and trim settings. Make sure the chain isnt being thrown over off the big ring.

    There will always be rub in the small/small combo. This is the chain rubbing on the big ring not an adjustment issue.
    I'm left handed, if that matters.
  • jermas
    jermas Posts: 484
    If it's not any of the above, another possibility is the cable guide under the BB has worn. If your cables aren't internal, with the mech/cable connected, try pulling the cable downwards under the downtube by hand and feel for resistance.
  • jgsi
    jgsi Posts: 5,062
    You havent ventured info as to what FD?
    Have you routed the cable correctly as that is probably the reason for a difficult change.
  • @k-dog thanks a lot
    I've went through all the guides and even the parktool one couldn't explain what I did wrong with my front mech!
  • me-109
    me-109 Posts: 1,915
    Typically, if all else is ok, cable passing the wrong side of the clamping bolt.
  • david37
    david37 Posts: 1,313
    me-109 said:

    Typically, if all else is ok, cable passing the wrong side of the clamping bolt.

    THIS