gear problems

trail jacker
trail jacker Posts: 844
edited July 2008 in MTB workshop & tech
hi all
i recently changed my drivetrain on my bike, with a brand new chain, rear cassette and ne Deore LX mech, but have been plagued with problems. the latest is that when im in 1,1 , 2,1 , 2,8 , 3,8 the derailleur seems to want to shift away from the extreme gear to the next one in. im sure its something simple i'll need to do so any advice would be great! cheers

Comments

  • nicklouse
    nicklouse Posts: 50,675
    sorry in what gears?

    which gear in the front and what gear on the rear.


    what chain and what cassette?
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  • Anonymous
    Anonymous Posts: 79,667
    Sounds like the limit screws need adjusting on your rear mech.
  • trail jacker
    trail jacker Posts: 844
    (Crankset,rear cassette)= 2,1 , 2,8 , 3,8
    its an 8 speed shimano cassette (probs should've mentioned that :oops: !) and a shimano chain (dunno specifics).
  • Anonymous
    Anonymous Posts: 79,667
    Still sounds like the limit screws need adjusting on your rear mech.
  • trail jacker
    trail jacker Posts: 844
    the high/low ones? which direction should i turn them or is it another trial and error jobbie?
  • Anonymous
    Anonymous Posts: 79,667
    your mech should have come with detailed instructions.

    but, basically, if you loosen the screws then it will allow the mech to get to the extreme top, or extreme bottom of the cassette more.
    if my memory serves me correct, the H screw adjusts the top gear (smallest sprocket position) limit, and the L screw does the lowest gear (largest sprocket position).

    So, you need to adjust the screws until the chain will get to, and stay on, the biggest and smallest sprocket, but will not go past it, into the spokes, or into the dropout.

    The H screw is the easiest to adjust, since the mech is under spring tension, so you will actually see it move whilst adjusting the screw.
    When adjusting the L screw, the mech is under cable tension from the shifter, so you may not see a difference until you shift up one gear, then back again.

    I personally find it easier to adjust the limits by eye, with the chain removed. This way, you can push the mech over by hand, and adjust as necessary.

    hope that helps
  • trail jacker
    trail jacker Posts: 844
    nice one, cheers for that! :D
  • salsarider79
    salsarider79 Posts: 828
    H is for high, L is for low, High gears top ones, low gears small ones. Be very careful when adjusting cos if the rear mech goes into the spokes, it's gonna be very expensive...
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  • Anonymous
    Anonymous Posts: 79,667
    H is for high, L is for low, High gears top ones, low gears small ones. Be very careful when adjusting cos if the rear mech goes into the spokes, it's gonna be very expensive...
    Low gears are the largest sprockets. High gear, or top gear is the smallest sprocket. :roll: