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Thread: No Clutch Freeplay on K75

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  1. #1
    Rally Rat
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    No Clutch Freeplay on K75

    I've been a part of an unresolved discussion at http://www.motobrick.com/index.php?topic=4439.0

    Capture.JPG

    Carl and I have K75RT bikes and after transmission maintenance and reassembly we've both found it impossible to get clutch freeplay using the recommended procedure.

    It seems that with new clutch cables installed in the most relaxed configuration (adjustment screw on hand lever in all the way) resulting in a ~90mm cable length at the cable bottom, then the clutch lever #7 is already touching the piston/bearing/pushrod #1,2,3 even without the adjusting screw #10 installed.

    If the screw on the hand lever is unscrewed a few turns as recommended so that the exposed cable bottom length at the clutch lever is set to the recommended 75mm then the clutch piston/bearing/pushrod is depressed enough to perhaps slightly disengage the engine from the transmission.

    What are we missing?

  2. #2
    Benchwrenching PGlaves's Avatar
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    Check the lengths of the old and new cable sheaths. Are they the same?

    Most importantly, compare the lengths of the difference between each sheath and the cable within it. That is, how much longer is the actual cable than the cable sheath. Those comparisons will tell you if differences in the cables account for the difference. For example, if you have 6 inches of exposed cable length on the old and 5 inches of exposed cable on the new one - bingo.

    If there are no differences then you need to consider what changed in the clutch assembly.
    Paul Glaves - "Big Bend", Texas U.S.A
    "The greatest challenge to any thinker is stating the problem in a way that will allow a solution." - Bertrand Russell
    http://www.bigbend.net/users/glaves

  3. #3
    Rally Rat
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    Thanks, Paul.

    With about 90mm of exposed cable length at the bottom (spec is 75mm) it feels like the engine is engaged to the transmission 100%.

    If I adjust the screw at the hand lever at all, even a couple of turns, the push rod is depressed enough to disengage the engine from the transmission some.

    If I adjust the screw at the hand lever so that the exposed cable at the bottom is to spec (75mm) then the transmission is disengaged entirely from the engine.

    This is the case with the #10 screw just barely protruding through the threads in the clutch lever.

    It's weird.

  4. #4
    3 Red Bricks
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    I believe that your problem (and the other guy's on the motobricks forum) is that you are measuring to the wrong surfaces.

    The measurement is SUPPOSED to be from the end of the metal on the sheath to the BARREL on the end of the cable (Not to the swage on the end of the cable).

    With the lever end completely disconnected the cable should have about 125mm from the end of the sheath to the barrel:

    cable 2.jpg


    Properly adjusted, it should be 75mm between the same two points:

    cable 1.jpg




    Last edited by 98lee; 06-16-2013 at 05:07 PM.
    LONG MAY YOUR BRICK FLY!

    Ride Safe, Ride Far, Ride Often

    Lee Fulton Forum Moderator
    3 Marakesh Red K75Ss
    Mine, Hers, Spare

  5. #5
    3 Red Bricks
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    OR

    You have an incorrect cable that has this dimension less than 24mm:


    cable.jpg



    LONG MAY YOUR BRICK FLY!

    Ride Safe, Ride Far, Ride Often

    Lee Fulton Forum Moderator
    3 Marakesh Red K75Ss
    Mine, Hers, Spare

  6. #6
    Rally Rat
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    Thanks, Lee.

    I was measuring it properly. When installed the max possible sheath to barrel distance is about 90mm. If I adjust that using the hand lever screw even a little, the clutch lever starts to depress the push rod.

    I'm in the process of removing the transmission from the bike now so we'll see how things look.

  7. #7
    Rally Rat
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    Here's what the lever-to-piston point looks like at rest.

    The piston is inserted "finger tight". I suspect it should be flush with the housing?

    P1020906.jpg

  8. #8
    3 Red Bricks
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    Quote Originally Posted by timtyler View Post
    Thanks, Lee.

    I was measuring it properly. When installed the max possible sheath to barrel distance is about 90mm.
    Measure it with the lever end completly disconnected and the cable not going through the adjuster. You should get 125mm.


    LONG MAY YOUR BRICK FLY!

    Ride Safe, Ride Far, Ride Often

    Lee Fulton Forum Moderator
    3 Marakesh Red K75Ss
    Mine, Hers, Spare

  9. #9
    Rally Rat
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    Quote Originally Posted by 98lee View Post
    ... With the lever end completely disconnected the cable should have about 125mm from the end of the sheath to the barrel:
    Confirmed. It does.

  10. #10
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    No Clutch Freeplay on K75

    The suspense of waiting for a solution is killing me. I have read and reread your post. I cannot confirm whether the projection of the throwout bearing beyond the rear of the transmission is correct or the problem, but try adjusting the levers and cable by this procedure.

    1. Set the lower clutch cable exposed spec (75mm) on lever #7 in the parts diagram with the knurled adjuster at the hand lever.

    Make sure the lower end of the clutch cable outer sheathing metal end is properly seated in the correct position. The bolt on #7 lever with the 10mm head (#10), at the rear of the throw out bearing, should be loosened so as to not to be making contact with the throw out bearing. Clutch is fully engaged.

    2. Screw bolt #10 in by hand until it just touches the throw out bearing and hold with a 10mm box end wrench while securing the 13mm lock nut.

    Back the 13mm locknut back far enough back before screwing #10 in by hand so that your are sure that it is the bolt that is making contact with the throwout bearing. So far the clutch is fully engaged and there is no slack between the handlebar hand lever and the forward end of the clutch rod at the pressure plate.

    3. Set the cable freeplay at the handlebar lever to spec. (4mm?)

    Screw the knurled adjuster IN so that there is Freeplay in the cable before it disengages the clutch assembly. It is measured at the first place that opens when you pull the lever. You can almost do this by feel and not sight. This slack ensures that the whole clutch assembly is fully engaged and not preloaded or partially disengaged when the lever is out.
    Don't forget to set the knurled locknut on the cable adjuster.

    Hope this helped. Whatever the solution turns out to be, please let us know.
    Charlie

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