ignition timing adjustment methods

Discussion in 'Motorized Bicycle General Discussion' started by highseastravler, Mar 17, 2010.

  1. AussieSteve

    AussieSteve New Member

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    Offset keys were mentioned earlier in the thread, from memory.

    Got my new motor (generator) and did the first tests with it yesterday. It easily produced 66W at 16V, still nowhere near full rpm, so it's looking pretty good.
    Once I get everything clamped down safely, I'll do full rpm short-circuit current and voltage tests, then I can start on the regulator and driving mechanics.
     
  2. exavid

    exavid New Member

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    Interesting thought about timing changing with engine speed but if the system is triggering on the 0V crossing point I doubt it would change much if at all. When you consider the speed of switching a transistor and the much lower top rpm of the engine it doesn't seem like the CDI would really see a serious change. Since the engine idles around 1000-1500rpm or so and has a top speed of around 9000rpm that would only be a 1:9 - 1:6 ratio change in the frequency change of the ignition speed. Not all that much for the size of the windings in the magneto and components in the CDI.
     
  3. Goat Herder

    Goat Herder Gutter Rider

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  4. thimmaker

    thimmaker New Member

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    I have no idea what these engines look like in the magneto area, but it seems to me you should be able to slot the stator a little and attach some sort of external handle so you could start it retarded and advance as needed for speed, just like they did on the old Monark Supertwins from the 50s??
     
  5. 2door

    2door Moderator
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    The magneto rotor,(magnet) can be easily removed if you have the right tool. Ace hardware has a faucet handle removal tool that works perfectly.
    Caution: Prying on the magnet can actually bend the crankshaft. The shaft is only about 5/16" in diameter where the magnet rides and prying it, applying too much pressure on one side can compromise the crankshaft. Use a puller, or the faucet tool, to assure even pressure. There is also a woodruff key that can sometimes complicate removal of the magnet. Use care and patients and don't damage the crank seal behind the magnet. Also mark the magnet, inside-outside, so it goes back on the way it came off.
    Tom
     
  6. Goat Herder

    Goat Herder Gutter Rider

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    Yes if you flip that magnet around the motor will not run.

    Ace is the place I did not know they had Ace in Ecuador;):p
     
    #26 Goat Herder, Dec 15, 2010
    Last edited: Dec 15, 2010

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