How to correct Beta clutch drag.

Discussion in 'Trials' started by lineaway, Apr 5, 2019.

  1. lineaway

    lineaway Long timer

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    The Beta clutch has always had clutch drag, and there has been countless thoughts on how to fix this. This video has the answer, but it seemed nobody had knowledge of what was being accomplished.
    #1
  2. lineaway

    lineaway Long timer

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    I have looked at this video for several years, but never found a parts source for the shims. Today I installed a .5 mm shin pack which seems to cure the drag instantly. I may try another .25 more after the trials this weekend.
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  3. lineaway

    lineaway Long timer

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    It is a pretty simple thing Remove the clutch cover

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  4. lineaway

    lineaway Long timer

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    Remove all the spring bolts and pull the pressue plate.

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  5. lineaway

    lineaway Long timer

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    Install the shims between the two washers that are between the pressure plate and the flat bearing for the push rod.

    Attached Files:

    #5
  6. lineaway

    lineaway Long timer

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    The shims can be ordered through KTM. Why Beta has not had these parts available is just crazy.

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    #6
  7. Cascao

    Cascao Been here awhile

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    This work for shercco 2010?
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  8. lineaway

    lineaway Long timer

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    Here are the part number from KTM.

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  9. lineaway

    lineaway Long timer

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    As you can see it is a 16x25x0.25 shim. I ordered three as the video talked about 0.1 through 0.5 shims. 0.25 is all I could find. Some experimenting will be needed. Straight forward work and cheap at 3 bucks a shim. Somebody surely might find them cheaper. These were shock shims.
    #9
  10. lineaway

    lineaway Long timer

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    The theory would work. Have no idea on Sherco sizing.
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  11. Nobade

    Nobade Keep on keepin' on...

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    That's awesome! I'll give it a try on my Beta. The clutch fix on Trials Central made a big difference, and if this stops all the drag it will be like a new bike.
    #11
  12. Tryalsryder

    Tryalsryder Adventurer

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    Also make sure you're not overfilling the oil level as that will always make the clutch drag on a Beta. Never had to do anything to any of my 5 EVOs because of a dragging clutch.
    #12
  13. 10K

    10K Trail Runner

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    Mine will drag for a minute until the engine warms. Other then that, the bike is solid.
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    slicktop likes this.
  14. lineaway

    lineaway Long timer

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    You silly girl, the Beta has had clutch drag problems for not just a few models but three decades. Granted the last few years have been much, much better. But this mod makes the clutch work more like the diaphragm type clutches too. We have had three different distributors over that three decades and no one has addressed this cure. Here the cure was being used in Japan the whole time.
    #14
    joe cool likes this.
  15. Gordy

    Gordy SUPPORTER

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    :rofl
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  16. Junglejeff1

    Junglejeff1 Long timer

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    A good place to find such shims are suspension shops. Rick at cogent is a very friendly guy and could get most anything needed in shim stock.Unfortunately 0.30 is usually the thickest used but maby offroad truck guys might use thicker ones.
    #16
  17. motobene

    motobene Motoing for 49 years Supporter

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    Interesting. I never owned a Beta until 11 days ago. Seems really strange to have SO MUCH lash between the TO bearing and pressure plate. I mean it just seems obvious not to have so much!

    Recently the brain has been consumed and I've been furiously exploring a new rabbit hole:

    https://advrider.com/f/threads/2019...ngineering-experiences.1375977/#post-37376697
    Among the long string of learning experiences and setups, a 3-part clutch mod. Lineaway will chuckle. He's seen all three parts before:flug

    When I first rode the Beta beast I was like WT... on the clutch. Trials rider meets stiff lever that cannot not be adjusted in anywhere near not goofball-far out (which promotes whiskey clutch, as you in the know know).

    Using some old tricks and tweaks later, I am now the proud fickle fingerer of a truly excellent clutch. The slip zone is super predictable and I can creep up stuff with no shuddering or grab at all. Within a few degrees of lever sweep I have both a wide slip zone and full release, lever still a bit off the fingers around the grip, even with a cold engine. Not bad at all for mother-earth-ripping, drooling-knuckle-dragger bike with a helical compression springs clutch!

    Note how the clutch basket and big primary gear on the RR/RR-S Betas are one integrated steel unit, as with the diaphragm clutches in trials bikes. I think that kind accuracy in a clutch helps to avoid drag.
    #17
    Kiharaikido likes this.
  18. Bluetonguejak

    Bluetonguejak Pretend racer

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    The clutch on both our 06 Rev3 and 03 Rev3 have cold clutch 'sticking' issues, both run completely different oils, but both can be freed-up by running through the gears whilst warming them up.

    The 03 clutch is fantastic, smooth, progressive and predictable, the 06 is a light switch and bloody hard (near impossible) to gradually slip, makes full-lock off-camber stuff ugly.:dirtdog

    The 03 does slip a little when hard accelerating in the high gears, but doesn't (noticeably) slip when in 1st to 3rd gears.

    Haven't had the clutches out to inspect measure and/or do clutch plate mod yet, but very interested in a 'fix' for the light switch clutch - i don't want to have to re-invent the wheel (clutch):ear
    #18
  19. lineaway

    lineaway Long timer

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    The `03 needs a clutch no doubt. Hard to say why the`06 is a light switch. The clutch hub itself could be grooved from wear, so not very progressive.
    #19
    Bluetonguejak likes this.
  20. motobene

    motobene Motoing for 49 years Supporter

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    Storage-time sticking happens after the plates have been used enough for them to polish finely the mating surfaces of the plates. The clamping force of the springs will push out the oil between the very closely mated surfaces and they will adhere together. You may have sit idling during warm-up with the clutch lever pulled to re float the clutch. Sometimes they refuse to un stick until you ride the bike with the clutch in and give the throttle a good twist in like 3rd gear.

    You can restore your clutch to non sticking by scratching the fiber and metal plates up with a fine emery paper. Don't remove any significant fiber plate material you just need to scratch the surfaces in random directions to remove the polish. The imperfections will retain oil and storage-sticking will go away a while. If you under-do the scratches, sticking may return sooner than you would like.
    #20
    Bluetonguejak likes this.