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  1. #1
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    chain is hitting the outside cage

    hi all. i am very new to bike maintenance and I was needing some help!

    my chain was on the highest chain ring and smallest cog on the rear and my chain was touching the outside cage of the front der. I tried slightly turning the high/low limit screws, but it didn't seem to do anything.

    Secondly, I unscrewed the hex of the actual front der to see how it works, but I am guessing the tension on the cable was too tight so I had an extremely tough time trying to get it back on. Do you suggest that I remove the tension from the cable before all this?

    I really want to learn how to do my own front/rear der adjustments and more. Thank you for your patience and help.

  2. #2
    dru
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    Your cable tension on the front derailleur is too slack. (I'll explain why in a bit) The limit screws do exactly what their name says: they limit the physical movement of the derailleur inward (low limit screw) and outward (high limit screw). The limit screws have nothing to do with cable tension. If your chain is rubbing the outside plate and the high screw does nothing to help when you loosen the screw, the cable tension is too low (your shifter cable is too slack).

    To set up your front derailleur, loosen the cable clamp and put the chain on the small front ring and on the big cog on the rear wheel. Make sure the left shifter is in 1st, and set the barrel adjuster one full turn out. Check the low limit screw and turn it until the cage is centered over the chain. Take a pair of pliers and pull the cable tight wher it pulls through the clamping nut. Snug up the clamping nut. If the cable still has some slack use the barrel adjuster. Try a shift from 1st to 2nd, and back and if it isn't shifting correctly use the barrel adjuster until it does. Try shifting up to 3rd. It should go, but if it doesn't loosen the high limit screw until it does. If it does shift to 3rd and the chain falls off the big ring, tighten the high limit screw until the cage will only move outward enoough to accomplish the shift.

    Good luck, it is a bit tricky to get right.

    If you move the derailleur cage in and out without a cable you'll clearly see how the limit screws function. If you watch carefully in 2nd gear and turn the barrel adjuster you'll see how cable tension affects the positioning of the derailleur cage relative to the chain and rings.

    Drew
    occasional cyclist

  3. #3
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    I am not the original poster but thank you for an informative lesson

  4. #4
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    awesome. i feel like you just taught me more than 70% of the der adjusting. One problem I had was that I loosened the clamp hex bolt, but nearly ripped off my hand because I didn't know the cable was still that tight. Would you suggest that I completely remove the cable that's being held by the hex? And then removing the clamp would be easier?

    Thank you for the good lesson

  5. #5
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    alongside with this, I have found a pretty good website: How to Install and Adjust Your Front Derailleur | Singletracks Mountain Bike Blog

  6. #6
    dru
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    Quote Originally Posted by swl7 View Post
    One problem I had was that I loosened the clamp hex bolt, but nearly ripped off my hand because I didn't know the cable was still that tight.
    The reason you had trouble is because you loosened the cable while the derailleur was in high gear. Put it in 1st before loosening the clamp. Make sure the chain is on the small ring too. Once you've set up the low limit screw then you should pull the cable taut with a pair of pliers and then snug up the clamp.

    The link you provided is good, use it by all means!

    Drew
    occasional cyclist

  7. #7
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    Was having the same issue. Thanks for the great info dru!

  8. #8
    dru
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    Quote Originally Posted by Trav_Rad View Post
    Was having the same issue. Thanks for the great info dru!
    No problem at all. Glad to help

    Drew
    occasional cyclist

  9. #9
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    Great post

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