adding to the collective:
found this exerpt from Myrons Mopeds: wiring diagrams below columbia
Invisible Forces: Notice that on the Colombia (and others) the tail light gray wire goes straight from the generator/magneto to the light, and not through the light switch. You would think the tail light would then stay on all the time. The small tail light generating coil is close to the larger head light generating coil. Somehow the magnetic field changes around the head light coil when the light is switched on, and that energizes the nearby tail light coil. So the tail light only works when the head light is working. This prevents tail light burn out caused by overload from a burned out headlight. On other 70’s mopeds, when their head light burns out, the tail light gets super bright, and dies.
which led me to parallel induction, which is different then the "Y" windings of a HT coil, as current isn't flowing directly thru the parallel leg.
a different Voltage pattern then i expected.
the bulb does not have time to cool down between spikes, so remains lit.
or it's not a simple parallel, instead using the magnets for current, somehow being dampened by the headlight coil?
and i get a F for presentation for this gross error, which no one caught:
Glenn Kuehn Wrote:
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> short why?
> to prevent the brake bulb blowing when the
> headlight blows.
should read taillight bulb, not brake.