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  1. #1
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    Jekyll rear suspension clunk

    After having ridden the bike (04 Jekyll 600 disc) for all of 5 hours I noticed a small clunk sound when I would unload the rear suspension by picking up the saddle and setting it back down. When I lock out the rear shock little bumps result in a clunk sound. I asked the wrench at the LBS about it and he said it is normal, that the bushings in the shock wear. This sounded like complete BS so I took the bike home and took things apart. It appears the bolt going through the rear of the shock is a tiny bit too small and can move around inside the shock bushings and the mount point in the frame. The problem I see is that with that slop every little hit gets transferred to the shock bushings (fine, they're replaceable) and the frame mount point (not fine, it is aluminum and will oval out).

    Anyone else noticed this? I tightened the bolt up a bit and the sound has gone away, but it is hardly the correct way to fix the problem. I'm serious considering enlarging the holes in the frame and pressing in bushings and using a slightly larger bolt (I'll machine one if I have to).

  2. #2
    Poser
    Reputation: direktor's Avatar
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    I adjusted my shock position yesterday and didn't tighten down the eyelet bolt as tight as it was, and noticed that clunk too.

    I decided the best way for it to be was to keep the bolt pinching the swingarm a little to kill the clunk, the theory being that if there's no play when things are unloaded, then the damage from the slightly mismatched parts will be minimized or eliminated altogether.

    At any rate, I've bene following these boards for a while and have never heard of a problem there...

  3. #3
    \|/ What 60 looks like
    Reputation: GaryS's Avatar
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    There should already be a bushing in the eye that the bolt goes through but I, like direktor, have found that if the bolt is little loose it will make a "clunk'". I now lightly grease the clevis on the inside where it rubs on the eye and torque mine to the specified 150 inch pounds (you do have a torque wrench don't you?). No more "clunk".

  4. #4
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    There is a bushing in the shock,but not in the frame. It is the frame I'm concerned about - every time you unload the suspension and follow it with a hit you have a stainless steel rod moving inside an aluminum hole that is too big. Over time the hole will oval out. Tightening it did help but it still doesn't seem like the optimum setup.

    Thanks for your concerns about my tools - yes, I have a torque wrench.

  5. #5
    \|/ What 60 looks like
    Reputation: GaryS's Avatar
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    Quote Originally Posted by tshrey
    There is a bushing in the shock,but not in the frame. It is the frame I'm concerned about - every time you unload the suspension and follow it with a hit you have a stainless steel rod moving inside an aluminum hole that is too big. Over time the hole will oval out. Tightening it did help but it still doesn't seem like the optimum setup.
    I agree but it will take a long time for that to happen and I'll probably be to old to ride by then.

    Thanks for your concerns about my tools - yes, I have a torque wrench.
    Good. I was amazed that tightening it with my 5/8" ratchet handle wasn't getting it anywhere near 150 inch pounds.

  6. #6
    cranktankerous Mainer
    Reputation: Toddski's Avatar
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    aaaa…. The dreaded clunk!

    On my 99’ Jekyll 900 and my 01’ 1000 both developed the clunk which originated in the bushing of the rear shock.

    Before you guys get all torque happy- try these tricks.

    First look at the bolt which travels though the eye. You could have one of the older bolts which have treads in the center it, over time the treads of the bolt will carve a nice little “clunk” into the bushing.-the fix is new bushing, new bolt.

    I recently sold my old Jekyll, and treated myself to a nice shiny new 04’ Jekyll 2000. Got two rides on it and ****! It has a clunk when I pick up the seat already! But wait..the shock lock ring thingy came loose..Tightend it up and the clunk is gone. Always check the tightness of the lock ring, crank that puppy down because this too can add “clunk.”

    Ok, so now I was curious about the treads on the bolt of the new bike. Took it out for inspection, and its nice and smooth in the middle with treads only on the end. For good measure I wrap a little white Teflon plumbers tape around the bolt where it contacts the bushing and shove it back into the hole. This trick works sweet!

    Also THIS IS IMPORTANT- when tightening down the shock bolt, take the bike out of the stand and place it on the floor, then tighten it up.

    Hope that helps.

    T
    Been there, done that... don't remember it.
    Bronson, Tallboy & Highball

  7. #7
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    Snap

    I too have a 1month old Jekyll 600 that clunks. Thanks for the information, I'll try this tonight as the clunk is fairly annoying.

  8. #8
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    Quote Originally Posted by GaryS
    I agree but it will take a long time for that to happen and I'll probably be to old to ride by then.



    Good. I was amazed that tightening it with my 5/8" ratchet handle wasn't getting it anywhere near 150 inch pounds.
    I'm assuming you meant 3/8" ratchet. 150 inch pounds is only at tad over 10 ft lbs - if you can't put that much torque on a ratchet it is time to stop working the legs on the bike and hit the gym for the upper body!

    I disagree about how long it will take to oval out the hole. If you do any amount of climbing in the locked out position every hit will have the bolt moving and slamming into the mount point in the frame - stainless versus aluminum will oval out the mount point quickly. It won't be as bad with the shock working because the shock will absorb the hit. I'm going to look into having a stainless bolt machined with a shank that is the exact size of the opening.

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