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  1. #1
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    2012 RockShox SID RCT3 Compression Not Functioning Properly

    I have a 2012 RockShox SID RCT3 120 mm, and the compression damper works like this:
    -locked out when the lockout knob is fully counter-clockwise (away from the lock icon)
    -no difference in threshold or open positions on the lockout knob at any low speed compression setting

    I have taken the damper off, and the oil is above the bottom of the damping unit. I took pictures of the the damper unit:


    When I turned the lockout know with the damper off the bike, the ports on the bottom part of the damper were closed fully clockwise, then part open, then full open; this seems to correspond to the damper working backwards to the icon.

    Maybe this is the way it is supposed to work? I really cannot tell any difference between the threshold and open, no matter what the LS compression setting is.

    Thanks,
    Kris

  2. #2
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    the low speed compression (four star silver adjuster) is completely separate from the lockout. In other words it will have an effect in all positions including open.

    The ports on the second piston (with the o-ring) should be completely closed on the lockout setting AND threshold setting. The difference between the two settings is how far the plunger going down the center of the damper has to move before it causes the lockout to blowoff (this used to be the floodgate adjustment on the older MoCo dampers but there are only 2 preset settings on the RCT3).

    It sounds like your threshold setting is not closing all the way so try turning it just a little bit past threshold towards lockout and you should be able to feel the difference.

    I have had to do the same on mine after I took it apart and put it back together. Havent really thought about how to remedy it but I'll let you know if I do.

  3. #3
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    Thanks Croakies. I will give the in the middle spots a try on the blue lever. It just seems like the lever is out of sync with what the damper is supposed to do... It goes the wrong way. I will likely fool around with it this winter.

  4. #4
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    ahh I misunderstood what the problem was. I can give two suggestions not sure if either will help because I do not have one in front of me.

    - pull the blue piston (it is being pushed back by a spring) until you can twist and rotate it 180deg and make sure it has fallen back into the slot on the adjuster end of the damper.

    - Make sure the grey plastic spring body is fully threaded into the black adjuster end of the damper.

  5. #5
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    Quote Originally Posted by croakies View Post
    ahh I misunderstood what the problem was. I can give two suggestions not sure if either will help because I do not have one in front of me.

    - pull the blue piston (it is being pushed back by a spring) until you can twist and rotate it 180deg and make sure it has fallen back into the slot on the adjuster end of the damper.

    - Make sure the grey plastic spring body is fully threaded into the black adjuster end of the damper.
    Hi Croakies,

    Thanks for the post. I finally got around to pulling the compression damper again. When I pull the blue piston and rotate it 180 degrees, I found that all the ports on the black piece attached to the grey spring tube has two ports 180 degrees apart. So 0 degrees and 180 degrees are the same.

    I can see that right about at lockout a huge pie-shaped port is open, and at the mid spot and the opposite of lockout it looks like there is one hole each. It is like a part is upside down, making the timing of the lever reversed. I don't really want to undo the nut on the bottom to pull everything out and put the piston that touches the black part in upside down, but it seems like it is either how things are mounted on the shaft or the black piece with the pie-shaped holes itself.

    I checked to see if the grey plastic spring body is fully threaded. It was so tight I couldn't dare turn it either way.

    Any other ideas?

    Thanks again,
    Kris

  6. #6
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    I pulled apart my damper tonight. Only 1 ball bearing went missing, and I found it in less than half an hour.

    It seems as if the black plate at the bottom of the spring tube is not placed correctly. I need to have the spring tube a little less than a quarter turn away from the top cap to have black plate "open" at the open setting at the lever. It looks like the "lockout" should function on both other clicks of the lever. It is the black top cap that has a locator that determines how much spring tube travel there has to be for the threshold and the lockout positions. Since both the lever detents and the locator are both in the top cap, I am pretty sure that this would work correctly as long as the black plate at the bottom's opening wasn't aligned with the top caps lockout or threshold settings.

    So what I am going to try is to install a small shim (around 0.25 mm) between the grey spring tube and the top cap. This would have the threads still fully engaged on the grey tube and have the black plate's port aligned with "open" and not approximately with "lockout".

    Does anyone have any other ideas or any thoughts as to why this could be bad?

    *edited for poor grammar*

  7. #7
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    In case anyone finds this thread and has the same problem, I resolved the issue. I shimmed the spring tube so that the holes in the black plate at the bottom of the spring tube matched the holes in the aluminum lockout plate when the lockout lever was in "open" or full counter-clockwise. For me, it ended up being very thin shim... I used aluminum tape, as pop bottle plastic was too thick. The timing for the blow off of the threshold and lockout depend on the black top cap.

    The force for threshold and lockout blow off is set by the spring tube travel, so hopefully the shim doesn't affect the force too much. I guess that this would allow you to tune (stiffen) the threshold and lockout based on the shim requiring more spring tube compression before blow off.

    Hopefully it holds up and the tube doesn't work loose because of the imperfect shim material.

    Kris

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