connecting a light to the magneto.

Discussion in 'Electrical' started by Norm, Jun 5, 2008.

  1. Norm

    Norm Member

    I have one of those generator lights with the friction wheel. Theoretically I should be able to power it off the magneto. It has only one black wire that conects the light to the generator. So the thing clamps to the fork. It's all metallic. well when I take the black wire from the light housing and connect it to the magneto (I've been connecting it where the wire to the kill switch is) It kills the engine so I know that's wrong. I'll post pics later this evening if need be.
    To resummarize, it's clamped to the bike frame, I disconnected the wire from the generator and connected it to the magneto where the kill switch connects. It kills the engine which is no surprise but I don't know where else to connect.

  2. eljefino

    eljefino Member

    maybe bulb draws too much current?
  3. Norm

    Norm Member

    Yeah, that's a possibility. But I think what's happening is, It's closing the circuit same as the kill switch does. In fact I'm sure of it. I'm wiring it wrong. I also think some other equipment is needed like a rechargeable battery and maybe a capacitor. My electrical knowledge doesn't go that deep. For now I'm just using it the old fashioned way and it works pretty good.

    thanks for the reply
  4. Bogaurd

    Bogaurd Member

    The way such a light usually works is to run positive through the wire from the generator to the bulb, and ground back to the generator through the frame (or the other way around, no difference).

    If you want to run this light off your engine, try this:

    Connect the wire coming out of the light to the white wire on your engine/magneto. The light *should* work when it is grounded against the frame - but may not. In this case, all that should be required would be a wire touching the metal housing of the light going back to the black wire of your engine/magneto.
  5. losenup

    losenup Member

    How many watt can u plug in to these type of egnines?
  6. There is a member that makes custom lights to run off the magneto. I believe with his it is the same as you are describing. I believe that if you start the engine and then turn the light on it might work...
  7. jared3377

    jared3377 Member

    I *believe* they put out 3 watts, but someone can correct me if I'm wrong. That's why I'm hesitant to even put one on (it's simply not enough wattage, and I'd like to BE SEEN by cars as well as be able to actually SEE the road at night, even on a dark street).

    Now, temporarily, I've got a Maglite hose-clamped to my handlebars, but I really don't like the look of it. I'm tempted to save up for one of these $100 systems, but they're kinda spendy; I also like the Wally-World-fog-light systems for their inexpensiveness, but the batteries are a little heavy and difficult to mount (for me at least).

    Someday I'll go with one of these options, but for now I mostly ride in the daylight anyways...
    Last edited: Jun 12, 2008
  8. Norm

    Norm Member

    Actually I've tried that misteright. I think the failure is that I connected the wrong wire. I used the kill switch wire and low and behold it kills the motor when connected.
    Thanks everyone for showing interest in my problem. Sorry, I haven't had time to mess with it recently. I'll run some experiments on it today or tomorrow.

  9. spunout

    spunout Member

    Last edited: Jun 15, 2008
  10. Marktur

    Marktur Member