SRAM Apex front derailleur problems

clickrumble
clickrumble Posts: 304
edited April 2014 in Workshop
I'm having great difficulty setting up the front derailleur so that it changes on to the larger sprocket without the chain coming off. I set it up of the bike stand so that it will just move up from the smaller to the larger sprocket, but then as soon I've reached the point where it will actually move the chain up, off comes the chain. I can just about get by on a ride with some very careful changing, but if I'm a bit heavy handed off comes the chain. Anyone any ideas what else I can try.. Replacement parts maybe...which ones crank, derailleur ?

Comments

  • DiscoBoy
    DiscoBoy Posts: 905
    I have no experience with SRAM setups, but I imagine that it has a limit screw in the same way that a shimano front dérailleur does, this limits how far the deraileur can travel (i.e. not onto the crank).

    Are you using a guide? Lots are available on youtube.
    Red bikes are the fastest.
  • clickrumble
    clickrumble Posts: 304
    Yes I've been using the limit screw to make the adjustments I have described above, sorry for not making this clear.
  • wishitwasallflat
    wishitwasallflat Posts: 2,927
    I've used Apex FDs lots with no issues are you sure it's aligned properly parallel to the rings and close enough to the top of the big ring (if memory serves 3mm)? If all that's correctI would check cabling.
  • StillGoing
    StillGoing Posts: 5,211
    Put the chain in the small ring on the front, big cog on the cassette. Without the cable attached, align the FD for height and direction. With the limit screw nearest the downtube, adjust the mech so that the chain runs with no interference just. Ensure the front shifter is in the correct position for the small ring and then attach the cable to the front mech ensuring it is taut. Change up to the big ring. Adjust the limit screw on the outside for fine adjustment. Change up and down a few times. Move the cassette to the small cog and check the shifting again. The adjustment with the limit screws can be very fine so don't get carried away with the amount you turn the screws.
    I ride a bike. Doesn't make me green or a tree hugger. I drive a car too.
  • paulbnix
    paulbnix Posts: 632
    I had exactly the same problem with my Apex FD.
    Mine was caused by the FD being rotated slightly clockwise (looking down).
    You can check with the chain on the large ring and the smallest rear cog, sight along the chain.
    The FD cage should be parallel to the chain though some small orientation may be required at a later stage.
    This assumes that the endstop and the FD height has already been set correctly.
  • clickrumble
    clickrumble Posts: 304
    Thanks for the suggestions, I'll give them a try.

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