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    Why wont my chain stay on big cog

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    12 Comments

    1. rsam487 on

      Spin the barrel adjuster a couple of turns until it does, can’t remember which way. But just do a quarter turn at a time if it’s your first time. It likely just needs a small adjustment if the other gears work fine.

      It could also be that the limit screws aren’t set up right, will see if anyone more experienced has a view on checking limit screws first before adjusting.

    2. Ccrook29 on

      Either you need to set your limit screw on the derailleur or you have a bent hanger

    6. Iocor on

      First guess would be low limit screw. Shift into a higher gear and then push the derailleur in as far as it will with your thumb while pedaling. You should feel a positive stop. If it stops before the big cog then it’s the limit screw.

    10. RhythmStiix on

      First thing to check- shift all the way outboard. On your first shift of the shifter to a larger cog, does the gear change? If so, it is the low limit screw. Shift into the second to largest cog and screw the low limit screw out (counter clockwise) 1/4 of a turn at a time. Check if you can shift into the largest cog after each limit adjustment.
      If you do not get a gear change on the first shift, it is the cable tension. Screw the barrel adjuster counter clockwise when looking at the barrel from the where the housing seats. Adjust the barrel 1/4 turn at a time until you get a proper shift out of the smallest cog in your first click of the shifter.

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