Bad vibration all over

Discussion in 'Motorized Bicycle General Discussion' started by sofasurferlinux, Jul 10, 2009.

  1. sofasurferlinux

    sofasurferlinux New Member

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    I got my first build running now and I am so happy (see pics). But it vibrates really bad. And I noticed that the engine is actually moving off center a little. I used the rubber in the motor mounts. But how tight do I tighten the mounts? If I make them super tight it will make the mount to compressed that they won't absorb the vibration (I think) and if not tight enough the engine moves. What the proper proceedure?
     

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  2. Cabinfever1977

    Cabinfever1977 New Member

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    you want the mounts tight,but dont overtighten them and break a stud.
    even with the mounts tight the rubber will dampen the vibrations and will depend on the thickness of the rubber and what its made out of.

    loose mounts will cause more vibrations,plus if the engine moves the chain will come off.
     
  3. Creative Engineering

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    If it is vibrating really bad, at all RPM, you have a defective engine.

    Jim
     
  4. sofasurferlinux

    sofasurferlinux New Member

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    Do you have a better recommendation for the rubber than the inner tube pieces?
    Defective engine!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!1
    Please don't tell me that.
     
  5. Cabinfever1977

    Cabinfever1977 New Member

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    i use old handle bar rubber grips that i cut in pieces to fit my mounts.
    they got rid of most of my vibrations.
    make sure your mounts are tight,but dont overtighten your nuts or studs will break.

    my bike vibrated like a amusement park ride before i used rubber on my mounts,now i have almost 0 vibrations at all speeds. plus i change my peddals for rubber exercise bike peddals and i wear boots when i ride.
     
    #5 Cabinfever1977, Jul 10, 2009
    Last edited: Jul 10, 2009
  6. Creative Engineering

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    If the engine is vibrating badly through the entire RPM range...you have a bad engine.

    No amount of rubber, or rigid mounting, is going to make it go away.

    A lot of these engines will have a bad vibration at a specific RPM. This vibration will dissipate as the engine RPM's increase or decrease.

    Some vibrate mid-way when accelerating up to cruising speed.

    In other words, you leave from a stop and a bad vibration occurs at 10-15MPH and subsides once you reach 20-25MPH...this is normal for an engine that is out of balance. This is just an example...gearing, tire size, and the RPM that the vibration occurs, will dictate the actual MPH where it happens.

    Some of these engines are very smooth until you hit a high RPM. Again this is normal for an engine that is out of balance.

    Considering the cost, I have no problem living with an engine that runs smoothly at cruising speed.

    If it vibrates like the dickens all the time...the engine is defective and will need to be replaced.

    Jim
     
  7. Pitchfork311

    Pitchfork311 New Member

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    Who did you buy your engine from?
     
  8. sofasurferlinux

    sofasurferlinux New Member

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    Bought it from PowerKingShop on ebay.
     
  9. Cabinfever1977

    Cabinfever1977 New Member

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    does it vibrate all the time or just at certain speeds.
     

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