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Sram X7 2x10 front derailleur adjustment - cannot get right

neatsneats Posts: 7
edited March 2013 in MTB workshop & tech
The bike is a 2011 Specialized Epic 26er with direct mount Sram X7 front derailleur, X9 shifter on a SRAM Carbon S-2200, 10-speed XC double crankset. Totally unchanged from new, no upgrades. Been ridden hard for 1 year, probably 4-6 times a week.

This bike has always had an issue with the chain rubbing the cage on the outside when in the outer/big ring, so much so that the old chain was worn away on the outside from the friction. Has also had problems dropping the chain off the big ring, no doubt due to this.

Just got a new chain and chain-rings for the new season, and replaced the cables but just cannot get the front derailleur to move far enough out to not rub the chain.
I've followed every step in the park tool book for the adjustment of cable tension, barrel on shifter, limit screws but cannot get the cage to move far enough out on the big ring. I've read the book, watched several videos and afaik I'm doing all the right things - I've replaced many front derailleur cable before successfully.

My only though is to replace the derailleur or shifter or both.

Any advice or ideas please? thanks

Posts

  • The RookieThe Rookie Posts: 27,804
    The cable moves the mech, the stop stops it, so either you haven't got enough cable 'tension' or the stop is in too far.
    Current steed - Whyte T129, 2013 frame, mongrel Revelations, Giant dropper, Stans S1 wheelset. 12, Magura Trail Sport brakes, 1x11. 12.8Kg
  • neatsneats Posts: 7
    The cable moves the mech, the stop stops it, so either you haven't got enough cable 'tension' or the stop is in too far.

    The H limit screw is so far out its not stopping anything, I've checked this. The cable tension is correct in that it should not be noticeably tight in the inner chain ring. However increased cable tension was something i already tried, I have tightened it as much as possible in the inner chainring position and still the cage does not move out far enough for the chain not to rub when on the outer ring.

    So I have tried maximum cable tension, doesnt fix it, and maximum setting for the H limit , doesn't fix it.
  • The RookieThe Rookie Posts: 27,804
    Cable tension will be wrong if the low stop is set too far out, keep increasing the cable 'tension' (actually length) until it's right in the larger gear, if it causes no issue in the lower, then that is the correct length, read park tools, how you say you are doing it now is wrong.
    Current steed - Whyte T129, 2013 frame, mongrel Revelations, Giant dropper, Stans S1 wheelset. 12, Magura Trail Sport brakes, 1x11. 12.8Kg
  • 97th choice97th choice Posts: 2,222
    If you are not confident then a quick visit to your LBS will sort it, and will be far, far cheaper than randomly replacing parts
    Too-ra-loo-ra, too-ra-loo-rye, aye

    Giant Trance
    Radon ZR 27.5 Race
    Btwin Alur700
    Merida CX500
  • neatsneats Posts: 7
    If you are not confident then a quick visit to your LBS will sort it, and will be far, far cheaper than randomly replacing parts

    Well all I can replace is the front derailluer and the shifter, so not really random.
    A new x9 front mech is about £29 online, or from LBS will be RRP and £45
    A new x9 shifter is £39 online and from LBS with be RRP at £69

    LBS labour will be min £25.
    So i could replace both myself for £70, or risk the LBS and get stuck for between £25 and £140.

    Plus LBS will likely be a week before they can look at it.

    So how it will be far far cheaper i don't know.

    Its not about confidence.
  • 97th choice97th choice Posts: 2,222
    My LBS does it for 8 quid, they will do F+R for £14.

    I don't know where you shop but they appear to have see you coming, plus based on the above you could spend £70 and still not have it working right.

    Try ringing around and ask what the price is to set up and index your front mech.
    Too-ra-loo-ra, too-ra-loo-rye, aye

    Giant Trance
    Radon ZR 27.5 Race
    Btwin Alur700
    Merida CX500
  • The RookieThe Rookie Posts: 27,804
    This looks like a simple indexing issue, swap the bits and either you'll still index it wrong and still have to 'fix' it, or you may get it right, but I'd sort the indexing first.

    Indexing the front is not like the rear, there is an element of trial and error and finding the sweatspot for cable tension.
    Current steed - Whyte T129, 2013 frame, mongrel Revelations, Giant dropper, Stans S1 wheelset. 12, Magura Trail Sport brakes, 1x11. 12.8Kg
  • neatsneats Posts: 7
    This looks like a simple indexing issue, swap the bits and either you'll still index it wrong and still have to 'fix' it, or you may get it right, but I'd sort the indexing first.

    Indexing the front is not like the rear, there is an element of trial and error and finding the sweatspot for cable tension.

    Yes this is what I thought but a few of use have had a go on this and got nowhere. We have about 15 bikes so gear indexing and re-cabling is something we do often. I wonder if the cage on the mech has been bent, it looks slightly "off" but its hard to say for sure.
  • The RookieThe Rookie Posts: 27,804
    Is it poorly adjusted for height or toe (not parallel to frame)? If it's a clamp mount, adjustment is easy.

    When you say the chain comes off the big ring, is that to the small ring or off the outside?
    Current steed - Whyte T129, 2013 frame, mongrel Revelations, Giant dropper, Stans S1 wheelset. 12, Magura Trail Sport brakes, 1x11. 12.8Kg
  • neatsneats Posts: 7
    Is it poorly adjusted for height or toe (not parallel to frame)? If it's a clamp mount, adjustment is easy.

    When you say the chain comes off the big ring, is that to the small ring or off the outside?

    Its a direct mount so height is fixed I think - I'm not sure if it is totally parallel to the frame, the cage does look slightly off - is this adjustable? As its direct mount Im not sure if there is any adjusment possible, i.e. it cant me moved higher or lower and cannot be rotated to adjust the parallel'ness . this is why I was going down the line of replacing it.
  • The RookieThe Rookie Posts: 27,804
    Have you got photo's of the height and alignment?

    Have you tried adding enough tension to get it to shift and then seeing what happens?
    Current steed - Whyte T129, 2013 frame, mongrel Revelations, Giant dropper, Stans S1 wheelset. 12, Magura Trail Sport brakes, 1x11. 12.8Kg
  • neatsneats Posts: 7
    Have you got photo's of the height and alignment?

    Have you tried adding enough tension to get it to shift and then seeing what happens?

    I can get it to shift, and all but the smallest ring on the cassette is fine, is just the outermost/smallest on the cassette that makes the cage rub the chain. If I get hold of the front derailleur with my fingers and actuate it out as far as it will go then its perfect with 1mm gap from the chain and stays there. If I then change down a chainring and back up again the rub is there. Its like the cable is not pulling to its full extent or being snagged - brand new cable and outer.

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  • The RookieThe Rookie Posts: 27,804
    Aprt from the obvious surface damage that looks OK, side view for height?, looks like a couple of turns on the adjuster and it won't rub even in top?
    Current steed - Whyte T129, 2013 frame, mongrel Revelations, Giant dropper, Stans S1 wheelset. 12, Magura Trail Sport brakes, 1x11. 12.8Kg
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