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  1. #1
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    Reputation: Ottoreni's Avatar
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    Clunk sound? Help

    Well, here's the problem (if it is one?)

    Everytime I compress the Marz Marathon s fork on my Burner, I hear this kind of deep clunk sound. Not to loud, but it is a noticeable sound. Once compressed, I can push it down repeatedly, and hear no sound. Now if I unweigh the front tire ( by lifting it off the ground) and then push the front end down again, I get the noise.

    I don't know if it is the fork, the headset or what?

    I have retightened my stem, after I preloaded the headset again, so that my spacers do not move (they were starting to move).

    Any opinions?

    I will most likely go sometime this week to my LBS (55 minute drive ), if I can't get rid of the sound.

    Anybody have a theory or suggestions that will save me a trip and money?
    You cannot go against nature, because when you do, its part of nature too.

  2. #2
    No, that's not phonetic
    Reputation: tscheezy's Avatar
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    It is often the coil in the fork. It deflects to the side and taps the stanchion wall. Try opening the top cap, compressing the fork a little, and turning the spring 90 degrees. That is sometimes enough.
    My video techniques can be found in this thread.

  3. #3
    ... I guess you won't be
    Reputation: jokermtb's Avatar
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    when you do this, is the front brake locked? or not.....and, just curious, but are you running a Thompson stem w/ the cylindrical wedge clamping gizmo?

    If your answer is brake locked w/ Thompson stem....I'd say the stem is the culprit. Put a cheapo on instead and try to recreate the clunk.
    Yes, we do indeed rock...http://www.myspace.com/spokedrunkies

  4. #4
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    Yes and Yes

    I had a Thomson stem and it always seemed that the spacers under the stem (10mm and 5mm) were tight when I preloaded the headset and tightened the stem bolts according to Thomson's torque #, but after a 1/2 dozen rides the spacers seemed to be looser than when I set everything up.

    Now I have a RF prodigy stem.

    It will make that noise with the front brake too.

    Do you think it has something to do the stem headset interface?

    What I am scared is of my headtube becoming ovalized.
    Thanks!
    You cannot go against nature, because when you do, its part of nature too.

  5. #5
    ... I guess you won't be
    Reputation: jokermtb's Avatar
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    If you have an old rigid fork lying around [or on another bike], try putting that one on and testing to see if the clunk is coming from the stem/headset area - this way you take the fork out of the equation.

    Curious - how old is your headset, and what kind is it....and are you using carbon spacers.....?

    Longshot - check to see if the bolts securing the disc to the hub are loose....this would cause a brake induced clunk sound also.....

    Lastly, if the big bushings in your marz are shot, you'll notice the fork will clunk slightly w/ the brake on when you rock it forward/backward w/ brake on.
    Yes, we do indeed rock...http://www.myspace.com/spokedrunkies

  6. #6
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    Eureka! .........Strangest Thing (long)

    [SIZE=5]Well, I started by removing the fork from the frame. Checked the headset cups. Pulled and tugged on both of them. Tight as can be.[/SIZE]

    [SIZE=5]Then I went to check the crown race, that's when I noticed the clunk sound. I moved the fork around and noticed the sound again. It seemed to be coming from the ETA side leg. I thought that something must be loose inside. [/SIZE]

    [SIZE=5]I removed the bottom nut, drained the oil, and pulled out the ETA side cartridge.[/SIZE]

    [SIZE=5]Everything was intact, except the spring had a lot of play. It moved freely between the top-black spacer and the bottom seat on top of the ETA cartridge (1-2mm play). I can easily see it hitting the inside of the fork. This amount of play cannot be normal, and I did not recall the fork doing this when it was new.[/SIZE]

    [SIZE=5]I removed the top cap, and with a 10mm or 9mm wrench, tried to tighten the red nut at the top. It didn't feel like I was doing anything, but sure enough, I was able to remove the play and the spring had some pressure against it. [/SIZE]

    [SIZE=5]Now I hope it stays put. I would hate to have that sound and play come back in a few months. [/SIZE]
    You cannot go against nature, because when you do, its part of nature too.

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