Magneto voltage

I'm not sure it's not a ..... Forgot the name those are not DC units the magneto is an AC unit burn out some test kits experimenting .
 
If you use a bridge diode and convert your ac to dc that the coil makes. Put a 5v voltage limiter after that and a 3s lipo charge board. I used 18650 lipos. Runs all your lights with little effort if there led! $5 Diode, 5x for $5voltage limiter, LIPO charge board 3s 2x $5
?????????????? I think I'll have to back to school, just to keep up with the lips and such.
 
?????????????? I think I'll have to back to school, just to keep up with the lips and such.

I think I can explain better since I know what this dude's talking about and I'm planning a similar setup.

So normally, the output on the red wire from your magneto is alternating current. This works okay for incandescent lights, but they draw a lot of power and tend to drag down the motor. LED lights are a lot more efficient, but current can only flow one way through them, so alternating current is no bueno. What you need is a component called a diode bridge or bridge rectifier. What this does is take in the alternating current and spit out direct current.

Diodebridge-eng.gif


While the output is now direct current, it's not smooth, and it's probably not the right voltage. It looks a bit like this:

Bridge-Rectifier-Input-Output-Waveforms.jpg


The other component he was talking about is a voltage regulator. This will smooth out the pulsating DC and regulate it down to the needed voltage. In his case, it's 5V, since he's using it to feed a charger board for lithium batteries. For my setup, it'll be about 14V, since I'm going with a 12V lead-acid battery. (Lead-acid batteries can be float-charged until the cows come home and don't need a specialized charge controller; they're a good option if you're neurotic about minimizing potential failure points like I am.)

Hope I helped and didn't just make it worse.
 
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Your idea will not work with a pb battery. Already tried it! I even custom wound a coil to attempt it after stock coil failed The task as well. Your coil will be 6-7 volts at idle and in the area of 11-15 volts in upper rpms. Now this is in ac values. When you use a bridge diode you will drop volts in the conversion to dc as well. This coil does not produce the current needed to charge a 12v pb. Plus it's heavy to lipo weight. Lipo only needs a 1-3v a cell to charge. @ 5v input most 3s lipo boards love this voltage with maximum charge rates since there limited at 3v each cell as it alternates cells in bursts of 7 to 10 seconds each cell rest goes toward powering the board.
Which coil were you using, the stock one or the aftermarket alleged "12V coil"? This is the one I'll be using.

 
12v after market coil. You can't use the magneto coil it has no secondary coils. White and red are soldered at the same point on the mag. White is intended to go to a capacitor for older cdi coils. The "high performance" cdi has a ceramic cap already inside it making white wire useless. The 12v aftermarket coils are only 12volts when your motor is doing 8000rpm lol pretty much. About 6v in the 2500 range. Not like an alternator in a car where it produces a constant voltage any rpm. The light there are intended to run is one like they used for friction generators off the tire. Its a 6v incandescent lamp "not frame grounded" bobber type light. If you use a grounded light the primary coil with short and you bike won't run since your primary and secondary will share a common ground point which will always be opposite direction charges in ac form since the North and South of the magnet is passing by each coil at a different time. I have put light kits and to charge High power servo battries on a few 2storke 1/5 scale rc's and over the years to get more run time lol "few meaning lost count" but these bike motors are the same thing pretty much. Hope it helps some. The main thing most people can't understand and why there coils never work or there bike wont run is the secondary coil needs to be 100% isolated closed loop circuit after the lead leaves the case and the line wire off the coil. Nothing in the light system can share a common frame mounted ground Period! Or your primary with short! Think of it as taking two batteries and touching there +to- and -to+ creating a short. Same idea just in ac current form!
I'm not sure I'm following. If my coil only has one black wire coming off of it, how do I make sure the ignition and accessory coils don't share a ground?

(It looks like there's two in the link I posted, but it's actually two ends of one wire. I'm assuming the ring terminal is supposed to go on one of the screws holding the coil in, but now I'm not so sure.)

EDIT: Nevermind, I think I figured it out. Looks like I need to cut the small wire that commons the lighting coil with the ignition coil.
 
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The ring terminal gets screwed to the motor with the screw that holds the coil on. All the grounds can be joined together and attached to the bike with one common terminal. In your link, the red wire isn't used.
 
Neither the lighting or the added aftermarket coil are very well suited for a charging circuit as the lighting coil is 6v and 3 watts and the aftermarket coil is 12v 6 watts which means they are both only 0.5 amps. Lipo cells are meant to charge at 1-3c for regular 18650 cells so if low capacity of 1000 mah they need 1ah min for charging and not at 5v,that's ok for a single cell but a three cell pack is 12.6v fully charged and that you will never see from these above setups! A lead acid 12v battery requires 14v for charging fully and again these will never see it so the life span of the cells or battery will suffer!
 
What is the maximum charging voltage for a 12 volt battery?
A typical 12-volt lead-acid battery must be taken to approximately 14.2-14.4 VDC before it is fully charged. (For 24 volt systems, double these figures.) If taken to a lesser voltage level, some of the sulfate deposits that form during discharge will remain on the plates.
Lipo cells are 3 volts when dead! and 4.2 v when fully charged, if you have 3 cells in series then it's 12.6 v and requires balance leads to be done properly or the life of the cells will be greatly shortened. If they are parallel then they are seen as 3-4.2v with increased capacity, your board does NOT step up the amperage and when there is only 0.5 a available how does it get 1.5a in burst's?
I use lipo cells every day and use a Hyperion charge system that shows the charge voltages out along with the amperage in real time through out the process and you are wrong! I use lipo cells to power all my rc stuff and my ebike if you want this type of cell to last they have to be used and charged properly!
 
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