Simple Question?.......

Discussion in 'Motorized Bicycle General Discussion' started by jowens, Sep 14, 2011.

  1. jowens

    jowens New Member

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    I believe my magneto is burning out my CDI's, is this possible?.......how do I correct it?
     
  2. decoherence

    decoherence New Member

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    is there water inside the magneto area?
    also magnetos prefer to be shorted than having an open circuit.
    "what does that mean?"
    well, notice how the kill switch shorts the blue & white wire to kill the engine. it is normally an open switch that closes to short.
    instead of just a blue wire running through the switch. a normally closed switch.
     
  3. jowens

    jowens New Member

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    Thanks for the reply Deco,
    There is no water in the magneto area. The reason I believe the mag is burning my CDI is that this past thursday I was not getting my bike to start, it would sputter a couple of times but wouldnt run. I had an extra CDI so I swapped it and cleaned the spark plug thinking I wasnt getting spark. Low and behold it fixed the problem immediately and the motor ran perfect. Today I am travelling down my street after porting my intake and the thing quits again. Try starting it as Im peddling back to the house and it sputtered once then nothing else. Its once again acting like theres no spark. I do not have a kill switch hooked to my engine.
     
  4. decoherence

    decoherence New Member

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    hmm. i have only had a problem w/ my mag. it was my own fault for driving through deep puddles.
    there probably better answers but i would say get another mag.
    from my understanding cdi's don't break that easy.
    the system is simple just a mag, cdi, & sparkplug.
     
  5. scotto-

    scotto- Custom 4-Stroke Bike Builder

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    You may also want to check your spark plug gap, if the gap is to large you can have problems like that as well. Just trying to help, sometimes it can be the simplest things that cause problems. Or even a faulty spark plug for that matter.

    dnut
     
  6. decoherence

    decoherence New Member

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    sound advise scotto.
     
  7. jowens

    jowens New Member

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    Thankyou both for the suggestions.......I will check the gap on the spark plug tomorrow but when I cleaned it the gap didnt look off to me......I guess it will be a decent try to swap the spark plug also......
     
  8. Venice Motor Bikes

    Venice Motor Bikes Custom Builder / Dealer/Los Angeles

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    I always remove the kill button from my bikes & remove the white wire from the engine... It helps prevent the ignition system from shorting out. (& I gap my plugs at .030")

    I also make sure the blue wire isn't exposed & doesn't come in contact with any part of the bike. ;)
     
    #8 Venice Motor Bikes, Sep 14, 2011
    Last edited: Sep 14, 2011
  9. jowens

    jowens New Member

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    Thanks Venice,
    That spurs another question, if I didnt remove the white wire and did not protect it from contacting something else could that ruin either the magneto or CDI along with shorting out the ignition or would it correct itself once the white wire did not touch any other metal and the short was corrected?
     
  10. decoherence

    decoherence New Member

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    yup. the white wire puts out voltage.
    cutting it off isn't a necessity. i just put heat shrink on it & tucked in back in it's hole.
    don't throw away your CDI's. you might have just been shorting out your magneto.
     
  11. jowens

    jowens New Member

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    So your saying I have possibly ruined my magneto?
     
  12. decoherence

    decoherence New Member

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    it is a possibility you have damaged it.
    it's ok. they are super cheap.
    when it comes to seeing a bare ended wire ANY TIME in your life, protect it. not just on your bike. wires carry electricity & the insulation is to protect the wire. if a wire is not protected, the insulation has no purpose & the wire is a liability.

    a stray spark can light dripped gas & torch your bits.
     
  13. jowens

    jowens New Member

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    Alrighty the answer to this breakdown is I did foul up the magneto. Swapped the magneto with one I knew worked and the bike is back to running like a champ! Its running even better than it did before because of the porting I did on the intake and exhaust JUST before the magneto went out on me. Once again THANKS AGAIN decoherence, scotto, and Venice for the support and suggestions. To everyone who is as green as I am to this hobby, make sure to cover up any exposed connections or wires on your MB's.
     

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