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  1. #1
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    Chain slips when going over bumps

    Hi,

    I have a Saracen Mountain bike with suspension (spring in middle kind) and I've just replaced the chain.

    Whenever I go across bumps or rough ground the chain starts to slip and I nearly fall off my bike if I'm standing up as the pedals slip too.

    What is causing this and how can I fix it?

    Thanks!

    This is the bike:


  2. #2
    Type 1 Racer rydaddy's Avatar
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    Most likely you need a new cassette to go with the new chain.

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    Quote Originally Posted by rydaddy View Post
    Most likely you need a new cassette to go with the new chain.

    False.

  4. #4
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    I had this exact problem, day before a race.

    The LBS examined it and the new chain wasn't fitting the shape of the old casset.
    the cassette had worn away to fit the old chain, and the new chain wouldnt fit on most of the teeth.
    most likely your cassette.

  5. #5
    M_S
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    Quote Originally Posted by rydaddy View Post
    Most likely you need a new bike to go with the new chain.
    My humble opinion.

  6. #6
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    Could be the new chain is to long maybe? You say its over bumbs, don't Dual suspensions have a chain growth type thing? maybe his derailure isn't keeping the chain tight enough

  7. #7
    :\ ping of death troie's Avatar
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    Thats just like saying everytime you get new tubes you have to get new tires too...

    Check the length of the chain first. I just put a new chain on my bike and I had to remove 7 links for it to fit correctly. If the cassette is worn then the obvious will present itself.

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    Thanks guys.

    I think the chain is too long.

    However, the last time I removed the links to shorten it, it became too short.

    Any hints for shortening the chain?

    Cheers.

  9. #9
    :\ ping of death troie's Avatar
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    Quote Originally Posted by eponymous View Post
    Thanks guys.

    I think the chain is too long.

    However, the last time I removed the links to shorten it, it became too short.

    Any hints for shortening the chain?

    Cheers.
    http://www.parktool.com/repair/byreg...mageField2.y=5

  10. #10
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    what about chain tension? Are you sure your derailer "spelling" ... is adjusted properly to your chain?

  11. #11
    Type 1 Racer rydaddy's Avatar
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    Quote Originally Posted by troie View Post
    Thats just like saying everytime you get new tubes you have to get new tires too...

    Check the length of the chain first. I just put a new chain on my bike and I had to remove 7 links for it to fit correctly. If the cassette is worn then the obvious will present itself.
    Obviously you need to shorten a new chain before installing. Maybe I should not have assumed the OP did that. And, no it is not just like saying you need new tubes with new tires. That is a dumb comparison. All I am saying is if you wait too long to replace a chain, you will be replacing the cassette with it.

    From my experience, I had a new chain skip with a 2000 mi cassette (road bike) and there were no obvious signs of wear presented to me. The fact that the OP's bike looks cheap suggested to me that the cassette is probably cheap and worn out too.

    Either way it doesn't matter to me. I threw what I thought out there and you disagree.

  12. #12
    :\ ping of death troie's Avatar
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    Quote Originally Posted by rydaddy View Post
    And, no it is not just like saying you need new tubes with new tires. That is a dumb comparison.
    Ya dont say...

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