Blue wire Kill-switch/Anti-theft device.



For people who don't want to use(or don't trust) the white wire as a kill switch use the blue wire.In it's standard form the white wire carries a voltage which shorts the magneto to stop the engine.With the blue wire u can still have the white wire to run a taillight/headlight and still safely kill your engine.
Simply disconnect your white wire kill switch portion and splice into the blue wire...put an on/off toggle switch anywhere u like.IF concealed it also acts as an anti-theft device.

Recognition given to Large Filipino.
I'm a little obtuse so I don't get it. How does a blue wire kill-switch prevent the bike from being pedalled away by a thief?
This idea stemmed from a thread where the author (sorry. I forgot who) kept blowing magneto's. And I'm theorizing that the magneto's are failing because we are shorting it every time we push the kill button. It may be easier on the magneto if you just disconnect the blue wire using a toggle switch on the handlebar (and a SECOND hidden switch for the anti theft) This may in fact prolong the life of your magneto although I haven't any studies. I do know that other engines kill themselves by disconneting a curcuit rather than shorting it out.(example,your car)
There's also the question though as to resistance. Would too long a blue wire going to the handlebar and back cause enough resistance to strain the magneto?
If I wanted a switch (I took mine off purposely) I would probably put it inline with the wire.
Fector,that's AWESOME! I bet you just did that. Does it work well?
That's actually a perfect place for that switch. You can still reach it while riding.
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They can still pedal it away(but they can't start it )

Large Filipino:
Yep your right man,i just did it thismorning after seeing your post...i was getting paraniod about the amount of ppl on MBc who were blowing their magnito's/CDI's.....WORKS PERFECT. :D
this is the coolest new HT idea i've seen in a while, and so simple it
makes you wonder how anyone ever got around to it...

yup, quit "killing" it altogether & just deprive the CDI with an inline toggle :)
(is there such a thing as a momentary-off button?)

this is a great contribution, guys :cool:


i recommend an inline for your whitewire light, too.

seems to me that the next logical step would be ground-strapping.

seems to me the best security would be a hidden toggle that does ground the blue-signal.
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Can I use a 3 prong switch?

I have one that has "power", "acc" (accessory to be powered), and a "ground" prong.

Do I just splice the black wires from the CDI & the Magneto, to the ground?

Or does one back wire have to be grounded on the frame?

If so, which one?

Which one to power?

Which one to ACC?

Holy carp I'm confused:eek::confused:
Were not grounding anything here. The way the electricals are set up,pushing the kill button grounds out the white wire. Grounding the white wire is essentially shorting out the magneto!
What were doing is having the wires just as they are. Connect coil to magneto Blue to Blue,Black to Black,white to accesories like lights or cap it off.
Now on the blue wire,simply attach a toggle switch. No grounding. Wire to wire.
When your running your bike just like in your car,the switch is ON. When you want to kill your engine,turn your switch OFF.
The way happy time has it is all backwards. Push the button ON to short out the white wire.
....I dunno. Maybe it's a China thing. :D

This is even the way motorcycles do it.
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Push the button ON to short out the white wire.
....I dunno. Maybe it's a China thing.
by making light, you underestimate our trade-"partners" (not a personal dig, an observation on current events) & they are counting on that (research the issue)...i bet they make a lot more money selling individual magnetos.

again, this "mod" makes so much sense it's a wonder anyone discovered it ;)
I learned about shorting with lawnmowers. When you release the bail, the ground wire from the magneto is pressed against the flywheel.