Chain jumps - is this ok?

Discussion in 'The Garage' started by JustRon, Jan 11, 2013.

  1. JustRon

    JustRon ex-broadwayron

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    This is an '08 Husaberg and the rear sprocket and chain are pretty new. I put a new front sprocket on (15t), but it wouldn't fit with the chain slider, so I modified the slider. There's not much room around the 15t, so I was a little paranoid. I've never tried this with my 'berg, but I ran it in first gear on the stand, just to make sure everything looked ok. But, the chain is jumping quite a bit. So, I put the old sprocket back on (14t- still in excellent condition, shows no wear). I get the same jumping.
    When I give it a little throttle, it seems to jump a bit less, but still jumps a lot.

    Here's a video:
    https://picasaweb.google.com/117975012494739338237/Junk#5832002953261146322

    Not sure if that video will work, because my work blocks it for me.
    I posted this on Husaberg.org, and one guy said it's normal when the suspension is uncompressed. Tonight, I'll look for a kink in the chain, but I'd be very surprised to find one.
    Any ideas?
    #1
  2. sieg

    sieg Long timer

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    Looks fine, just engine surges. Load the chain/engine (drag the rear brake) and it will smooth out.<?xml:namespace prefix = o ns = "urn:schemas-microsoft-com:eek:ffice:eek:ffice" /><o:p></o:p>
    BTW the video works, now get back to work.:nono<o:p></o:p>
    #2
  3. groundrules

    groundrules Long timer

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    Oh hiya
    no chance you've got a sticky/frozen link on the chain, right?
    #3
  4. Switchblade315

    Switchblade315 Long timer

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    even seen what a chain does when you go over bumps. that looks like the rear tire is getting faster then the chain and pushing slack in it or a split second. and you might possibly have a stiff link but i say it looks normal. as suggested put just a little pressure on the brake and I bet it stops.
    #4
  5. JustRon

    JustRon ex-broadwayron

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    ^ I'll check that tonight. I think I would have noticed already, but I haven't specifically looked for it yet.
    And, I'll try applying the brake (I have this horrible feeling I'll put weight on the rear and the spinning wheel will catch the ground, heh.)

    I guess I just don't know how this should look. I assumed the wheel would spin and the chain would look pretty smooth.
    #5
  6. bomber60015

    bomber60015 Anatomically Correct

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    the video you posted looks very normal . . . . if your worried about weighting the scoot and dropping the tire to the ground (which, I agree, might be exciting), create drag on teh wheel (2X4 or some such) . . . . . . same affect.
    #6
  7. sieg

    sieg Long timer

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    Just push the pedal with your hand, or a long screw driver under the foot peg and over the pedal that will not weight the rear of the bike at all.:deal<?xml:namespace prefix = o ns = "urn:schemas-microsoft-com:eek:ffice:eek:ffice" /><o:p></o:p>
    #7
  8. anotherguy

    anotherguy Long timer

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    Big single torque pulses + typical drivetrain slack = jumpy chain. You oughta see my Tuono's chain on the dyno at 2500 RPM.
    #8
  9. JustRon

    JustRon ex-broadwayron

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    Took it for a test ride today with the bigger front sprocket, and all seems well.
    Thanks for easing my mind!

    (Third gear power wheelies take slightly more throttle with the bigger sprocket- I love this bike.)
    #9