Bar weight myth

Discussion in 'The Perfect Line and Other Riding Myths' started by Colorado_Rider, Jan 31, 2014.

  1. Colorado_Rider

    Colorado_Rider Banned

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    My ever since I started lightening my bars by removing the weights I've found the vibrations reduced by a huge amount. Discuss/argue/ignore doesn't matter to me I think it's BS.
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  2. OrangeYZ

    OrangeYZ Been here awhile

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    When I installed bark busters on my KLR I left the weights off because I figured there wouldn't be any difference. Made it five miles, said "This sucks," went home and found bolts long enough to put them on.

    On that bike it's true, I haven't had them on any others.
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  3. fast1075

    fast1075 Fasterizer

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    My experience has been that it depends on the frequency of the vibe and the type of bar. The bar end weights help a lot with high frequency buzz, but often to little for low frequency rocking couple.
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  4. FrogAndTrumpet

    FrogAndTrumpet Adventurer

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    I recently fitted (OK, for "fitted" read "bodged" :D) some KTM handguards on my SpeedTona, which entailed junking the bar weights. So far, I haven't noticed any uncomfortable vibes and buzzes in the 'bars - which is just as well because my bodge job means that I won't be able to remove the guards and refit bar weights very easily... :augie
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  5. Colorado_Rider

    Colorado_Rider Banned

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    This was on an I-4. A single or twin, I've yet to try it on, but the XR650L I had with just a bar, no weights didn't give me near the problems it should have considering how much is vibrated on the highway.
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  6. phreakingeek

    phreakingeek adventurer

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    on my DR650, the stock bars without weights were so bad that I didnt even make it 5 miles before going back home.

    My handguards now do the job of weights to keep the vibrations from turning my hands into leaden nubs at the ends of my arms.
    #6
  7. joexr

    joexr Banned

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    What the hell is a SpeedTuna?:rofl
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  8. FrogAndTrumpet

    FrogAndTrumpet Adventurer

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    A SpeedTona (with an "o" :wink:) is a Triumph Daytona that's been turned into a Speed Triple (usually as a result of a SMIDSY moment). :deal
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  9. joexr

    joexr Banned

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    :rolleyes
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  10. Red9

    Red9 Been here awhile

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    Yeah cause manufacturers were just looking for places to add additional weight...:rofl
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  11. godwinmt

    godwinmt They call me Crash

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    Bar weights cannot eliminate handlebar vibrations, they merely serve to shift the resonance point of the bars to some other point in the operating range. The 'vibrations' people notice are a resonance mode in the bars. You can shift where this resonance point is by either altering the mass or stiffness of the bars. Increasing the mass and decreasing the stiffness shifts the resonance point lower in the revs, and doing the opposite shifts it farther north.

    You by lightening your bars are shifting the point farther north in the revs. I imagine if you ride a little faster, you'll again find the point where the bars do vibrate, just not where you ride most of the time.

    It's Vibes...nothing more, nothing less.

    -M
    #11
  12. MacNoob

    MacNoob piney fresh

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    If the bars happen to resonate at a frequency that is some harmonic of the engine vibration, you will get vibrating bars. Bar end weights will change the resonant frequency of the bars so they will vibrate at a different RPM that may be outside your common RPM range, reducing the irritant.
    #12
  13. toates89

    toates89 Been here awhile

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    Frequency is equal to the spring constant over mass

    omega=k/m

    As mass increases omega decreases.
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  14. markk53

    markk53 jack of all trades...

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    And you've gained this great insight by removing the weights on how many bikes?
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  15. markk53

    markk53 jack of all trades...

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    Nah, they got a good buy on them and had to do something. Or maybe it was part of the "bold new graphics" the second year.
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  16. markk53

    markk53 jack of all trades...

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    He also has problems with the engine running rough, as Joe Walsh put it, "You can tune a piano, but you can't tuna fish."
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  17. Bar None

    Bar None Candy Ass

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    One bike was all he needed to prove his point.:rofl
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  18. Pantah

    Pantah PJ Fan from Boston

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    Exactly how does one "shift the resonance point of the bars to some other point of the operating range"?

    The guy asked a question and you invent some sort of scientific response for personal effect, yet useless to your audience.

    Too many people like you on this site.

    #18
  19. Night Falcon

    Night Falcon Adventure NZL

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    cool....another Myth Busting Myth Busted, busted myth thread :norton
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  20. tkent02

    tkent02 Long timer

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    How can this be useless? That is exactly what the weights do.
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