The Blue,the Black and the Ugly (White)

[Drunkskunk]

To charge the battery, you only "need" 2 things. AC to DC conversion, and Voltage regulation. the AC/DC conversion is easy. a diod in line between the white wire and the battery. Voltage regulation is also easy. a 7 volt Ziener diod can be placed in Parallel to the battery to prevent over charging. As long as the battery is a lead acid like a car or motorcycle battery, this is all you "need".

But its been stated that this is only good for 3 watts, or 1/2 amp. thats not much power. and since a battery doesn't charge at 100% effancy, you can't use 3 watts of power for lighting with a battery charger setup. And since 3 watts is max, you're better off not pushing the lighting over 2 watts. Thats functional, but not worth much effort for most people.

And so the speculation of adding a second magneto or generator began. and the end result of that tangent is yes, it can be done, and in the case of the HT electric start version, might be very easy. the starter is 12 volts, and if it can produce 5 amps, then the bike would have enough power to run a 55 watt motorcycle headlight

 

[duivendyk]

The **** "White Wire" plot thickens &thickens and has now the consistency of murky molasses.It has featured in different guises, as an output to power a light,or as a thing to put the kill switch on or to do both? (may be).It could well be that there are different variants around of generator coils, which depending on the manufacturer can behave rather differently,So that putting the kill switch on it works in some cases,but is not guaranteed to work allways,in fact may not work at all and even destroy the generator coil.There have been numerous instances of this happening lately,which prompted me to declare it off limits for that purpose.
We do know that the white output is a tap on generator coil, and depending on where it is located on it,closer to the black (ground) or to the blue(ignition)output it will behave differently.The closer it is to the blue output the more reliable it becomes as a kill switch,but the less suitable to run a light since the output voltage would be too high,in fact a light bulb would act as a kill switch which is hardly the intent.
The most reliable way to kill the engine is with the blue wire,but that is not without it's dangers,there is a few hundred volts ac there which it is potentially a lethal voltage.Anything to do with it has to be dealt with with CAUTION.This is probably the reason for the white wire kill switch in the first place ,it's much safer,but if doubling up as a 6 V output,it can become a questionable ignition killer.That's my best take on the situation.I could go into the theoreticlal reasons why this is so, but few people will be able to make sense out of any this.
The best that can be said is this:Follow manufacturers instructions.Using the blue wire for the kill switch function is guaranteed to work,but can be QUITE DANGEROUS.I have worked in a High Voltage Lab and am conscious of the inherent dangers under adverse (wet) conditions. Use quality components,protect against moisture,use reliable grounding

 

[Torques]

The throttle has the kill switch mounted on with it and there are two wires that come out of it. The diagram says to route the yellow wire to the blue wire and the other wire to the black wire. Isn't the twist throttle acting as a ground to the handlebars since there are two wires coming out of it?

 

[duivendyk]

Not really,but that does not mean that there's anything wrong with what you've got,the "hot side of the generator coil in the engine is connected to one side of the switch,the other side of it is connected via the black wire to the "cold" side shorting out the coil&killing the input to the CDI and thus the spark.Wether anything is grounded(connected to the frame) is immaterial really.You could ground the "floating" circuit by connecting the black wire to the frame someplace say at the engine or at the input to the CDI.What is frequently done is to use ground connections at different locations is to use the frame as a substitute for running a black wire,for instance you could make a connection to the handle bars at the twist grip and also have one at the CDI for instance..Now you don't have to run a black wire between the two the frame provides this for you.I am not a fan for these multiple grounds in something exposed to the elements.In a car, in a protected environment it's OK and saves having to run "ground" wires all over the place.As far as a bicycle is concerned you can make the case that a floating circuit is actually safer!,sitting on a wet saddle you are pretty much "grounded" to the frame, for you to get shocked a current path needs to be established through you to the frame,if the entire ignition circuit is not connected to it ,no current can flow.So if you manage to connect yourself to the blue wire you are now grounding the system but you are safe.It's currents that kill you, a couple of milliamps ac from your hand through your chest is enough to disable your heart's electrical apparatus.Spark outputs though unpleasant are not lethal because the the currents involved are only a fraction of a milliamp.Some high energy CDI systems could be dangerous though.

 

[Torques]

Thanks for your thoughtful repsonse. Well I guess I will reroute my wiring to what is in the diagram leaving the white wire with nothing attached to it, then attach a wire from my front light to the white wire and see what happens. I hope I don't hurt anything.

 

[duivendyk]

I called the white the "ugly",seems well deserved,if you have an VOM please measure at the engine, the resistance between white&black and between blue& black,with nothing else connected.I would like to know(I don't have a HT) If you have an open circuit your coil is shot.

 

[arceeguy]

Just would like to add that the "black wire" is "grounded" to the engine case and is not "floating". The connection to the frame can be made through the mounting clamps, or possibly even the chain/spokes. I installed a ground wire from the engine case to bicycle frame. I kill the engine by putting a 100 ohm resistor across the blue wire to frame using the kill switch. Shorting the blue wire to ground shouldn't cause any damage, but y'all have me paranoid about frying the CDI.

 

[duivendyk]

Is it actually physically connected to the engine block INSIDE the engine by the manufacturer ?.I didn't think so,but I have not been able to verify wether it is or isn't since I don't have a HT engine.If you disconnect everything on the black wire outside the engine and then measure a short to the engine or frame, you are right,if it's not you are wrong.You would not need to put a ground wire to the frame unless the engine was electrically isolated from the frame.If that were the case you would actually have a "floating" system unless of course you chose to connect it to the frame.All this "grounding" talk is a bit silly really,the bike is not grounded either,nor is your car for that matter.For the White Wire users play it safe and stick a fuse (1Amp slowblow should do) in the circuit !!

 

[arceeguy]

.....If you disconnect everything on the black wire outside the engine and then measure a short to the engine or frame, you are right,if it's not you are wrong.....

Uhhhhh, I'm pretty confident that I am right, otherwise I wouldn't have posted.

I wired the engine case to the bike frame because I wanted a positive electrical connection to the frame knowing that I was going to wire a headlight and kill switch using the frame as an electrical return.

 

[duivendyk]

Of course you are "pretty" sure,but are you absolutely 100% foolproof sure,because you actually checked.I was injured once because somebody told me that the interlocks on a transmitter had not been defeated and the high voltage could not come on.So I stick my hand in there to wiggle an EIMAX 1000 tube to try if I could bring the filament to light up.This was a beacon transmitter and a plane was running out of fuel and badly needed a bearing to land in a sandstorm.The 5 min. timer runs out and 5000 V dc + RF goes through my hand into my shoulder.I am thrown against a steel beam, big gash in my head my hand looks like a monstrous pop corn eruption and is paralyzed, but lo and behold the transmitter has come to life,both tubes are on and the plane later manages to land.So after that unpleasant experience I tend to be a bit sceptical about people who are "pretty" sure about things electrical.Once bitten etc.