CRF1000AT: bouncing front wheel at low speeds

Discussion in 'Land of the Rising Sun: ADV Bikes from Japan' started by PhaseShifter, Oct 1, 2017.

  1. PhaseShifter

    PhaseShifter Been here awhile

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    From 40 till 100 km/h, i am experiencing a bouncing feel in the front, like the rim or tire has a un-round form. Above 100 km/h it seems to disappear.
    Any other AT owners dealt with this problem also? if so, what was your/ the solution?

    DCT with 10k on the ODO, TKC70 front and rear, OUTEX conversion and balanced the wheels, perfect round rim and tire.
    #1
  2. Motociclo

    Motociclo Without motion, nothing.

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    My Af Twin has a similar thing. I use E07, I think it is the tyre. Only noticable at low speed on smooth surface. Have rebalanced, still there. Rim not bent etc.
    I have read others with 21 inch tkc 70 have had similar thing happen.
    I haven't noticed any ill handling, just a low frequency bounce. Bit odd.
    #2
  3. danptobin

    danptobin Been here awhile

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    sounds like you still have a heavy spot in the rim/tire combo. recheck balance.
    #3
  4. danptobin

    danptobin Been here awhile

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    low speed vibration (below 50mph) is typically bent rim or out of round tire. having a heavy spot that takes alot of weight (relative to the wheel tire combo) to counter can have a similar effect.
    #4
  5. joeywyn

    joeywyn n00b

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    Hi . Yep exactly same problem. Started with E07 being put on. Tried monkeying the suspension etc but have concluded it is the tyre. Did not happen with tkc80. Steve


    Sent from my iPhone using Tapatalk
    #5
  6. Crankarm

    Crankarm Adventurer

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    I have the exact same problem
    Tire is a TKC 80 with heavy duty tube, dealer "balanced" but I still have the low speed bounce
    #6
  7. michaeln

    michaeln What're YOU lookin' at?

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    I had the same problem after Konflict did my forks. Mine would be mostly smooth on smooth roads, but every few seconds there would be a series of 3 or 4 vertical oscillations of the front wheel. I discussed it with Alex and he figured it was an out of round tire. Sure enough, my worn Shinko 80whatever front tire was about 3/8" out of round. But the vibe I got was not a once per revolution one, it was more like it would hit a resonant frequency and then do the 3-4 jumps, then smooth out, and repeat.

    I did change out the worn Shinko, for a GoldenTyre GT723 (?) which was a tire Alex recommended highly. It did seem to lessen the problem, but it was still there. The tires were very carefully balanced, so that wasn't it. Turned out I did not like the GoldenTyre so replaced them with Motoz Tractionator GPs. Again, the problem was still there. I just figured that was some idiosyncrasy of the bike.

    Never did figure it out, and for other reasons, I sold the AT.
    #7
  8. dosveeled

    dosveeled Adventurer

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    Hate to be that guy, but bouncing front end was what started my fork issues. Thought tire balance. Took tkc off and replaced with stock tire and rebalanced. Still bounced. Checked for bent rim. Fork alignment. Took to local suspension guru and found excessive stiction. Hopefully not your issue. Look at the AT suspension thread. Again sorry for bringing it up but might be worth looking into.
    #8
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  9. michaeln

    michaeln What're YOU lookin' at?

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    Yep, I rather suspected stiction. Mine was before ForkGate was known. I would not be surprised if the out of round Shinko was a victim of the forks, rather than the cause of the hopping feel.

    Honda really shit the bed with those forks.
    #9
  10. PhaseShifter

    PhaseShifter Been here awhile

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    Thanks for reply guys!

    Today, i put the bike on the jiffy (8cm block under the jiffy to keep bike as up-right as possible) i lifted the front-end up and guess what.... first the fork didn't want to move up at al and sudden it popped up......:kat

    i guess i have to visit the Honda dealer.....:evil
    #10
  11. Motociclo

    Motociclo Without motion, nothing.

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    My forks don't have any stiction after recoat etc, and front tyre still has bounce.
    Your forks may be sticky, but that isn't causing tyre to bounce.
    #11
  12. dosveeled

    dosveeled Adventurer

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    Good to know about the recoat. Mine are out getting hard anodized now.
    #12
  13. dduelin

    dduelin Prone To Wander, Lord, I Feel It

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    You have to accept this is not unusual with stiff bias ply tires and I do not believe anyone makes a radial in 21" diameter. Triumph Tigers do this as well..
    #13
  14. KASUYAHO

    KASUYAHO Playing in the dirt

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    Mine does it too, i mentioned this to my tire guy and we are going to make a few changes.
    I am running a Pirelli Scorpion Rally on the front and a Motoz Tractionator on the rear which is a heavy tire.
    My tire guy seems to think it maybe from the heavy rear tire.
    It did this with the stock suspension and still does it with the upgraded suspension.

    I have noticed that on decel as this engine has very good engine braking, it will load the front suspension on decel.
    and the bounce will appear, on accel there is no bounce.

    Maybe going a lighter rear tire may stop the bounce ?

    It never did it with the stock tires.
    #14
  15. Zave

    Zave ******

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    I have the same issue at 60kmh or so then disappears i'm running 804's and just spooned them on.
    #15
  16. mcmann

    mcmann Motorcycle ADV enthusiast

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    IMG_9027.JPG
    #16
  17. MillennialFalcon

    MillennialFalcon Improvement starts with self

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    mcmann, I don't see front wheel bouncing in there so that seems pretty irrelevant. "Wobbling" is a technical term for unwanted "side-to-side" forces, OP has unwanted "up-and-down" forces.
    #17
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  18. PhaseShifter

    PhaseShifter Been here awhile

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    :y0! Yep!
    That’s how i see it too.
    #18
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  19. WIsixfitty

    WIsixfitty rock and roll the bones

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    Mines been bouncing from almost day one with the OEM tire. I'm fairly certain it's the stiction/fork issue.
    #19
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  20. Zave

    Zave ******

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    Mine has settled down since i changed the tire position wrt to the rim and rebalanced
    #20