Lighting from our magneto white wire

GoldenMotor.com
Sep 4, 2012
242
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America's Hi-five
A single diode simply clips off the negative ~7V part of the magnetos AC single so you are only drawing half the potential thus only half the power loss for generating power from the engine.

A full wave 4 diode rectifier turns that negative pulse to positive so you get both sides of it, all AC power supplies and even those little brink chargers you use for nay low voltage use this.

In short a pulsed trickle charge to you battery so not a constant drain and why you don't feel it so much.

Our DON'T USE THE WHITE WIRE stance is simple.
It takes power to use and store power.
You can do it with your little 2-stroke gas/oil mix engine at the expense of riding power and gas mileage, or use your home AC and charger and store a weeks worth of power in a little Lithium Ion battery for less than a penny and let your engine put all it's power to your wheel 100% of the time.
I hear what your saying, I just think there is a need for a counter point that lighting from the white wire is reliably, cheaply and easily achieved simply using a battery and a diode. I find it difficult to take that it robs the engine of any real hp. The white wire is its own winding, so it cant steal spark. The magnet and windings are tiny. could they steal more hp than a psi in the tire?
I do understand that if every little 1/100 HP is trying to be squeezed out then it isn't for you. I think the benefit outweighs the negatives in this case. Until the power demand exceeds what is available, or we can't get white wire magnetos anymore
 
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BarelyAWake

New Member
Jul 21, 2009
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Maine
Our DON'T USE THE WHITE WIRE stance is simple.
It takes power to use and store power.
You can do it with your little 2-stroke gas/oil mix engine at the expense of riding power and gas mileage, or use your home AC and charger and store a weeks worth of power in a little Lithium Ion battery for less than a penny and let your engine put all it's power to your wheel 100% of the time.
It is not "our" stance and it's definitely not a simple one.

I have personally used the dreaded white wire for lighting, for both headlight and taillight simultaneously, tapped directly w/o regulator, rectifier or battery - & while it isn't enough to power a gazillion lumen incendiary device, if done properly it can yield just enough to power an LED trim light for a taillight and a 6v flashlight bulb for the headlight.

Yes, of course there's far better headlights available but for the cost of a staggering 0.005hp (4w) it's good enough as a trim/indicator light, the output similar to the common "bottle gen" lights without the tire chafe or burn out issues. If ignition problems are experienced turn off the light to start and/or tighten the plug gap a touch.

It's just enough to provide a safety device you cannot forget to charge, won't drain out mid ride, or leave at home on that cruise that lasted a little longer then you thought.

Most of all it's an entertaining project to experiment with for the DIYer interested more in building then buying, which is more then anything else what these discussions are for. Success isn't guaranteed, but there's no harm in trying.
 
Sep 4, 2012
242
1
16
America's Hi-five




found my diode stash. Number says 5406.

I just don't want anyone to be discouraged from trying to make some light, it is possible. Decide for yourself whether the power is enough for your needs. There are a lot of creative people here.
 
Sep 4, 2012
242
1
16
America's Hi-five
Check out the full wave rectifiers at RS. Mine has worked faithfully for almost 3 years, rectifying 12V/5-6A. AND full wave rectification gives you twice the power for given demand. Less then $5.....
I'll have to check that out, until I add the headlight in I have an excess of power as is, but I'm considering adding a 7805 radioshack 5v regulator for my phone, and that could very well be the end of power available before the headlight even happens... A full wave stealing power from the cdi like a motorcycle highbeam switch in addition to the white wire might solve that at the cost of spark. Lets find out.
 

bigoilbob

New Member
Dec 15, 2013
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St. Louis, Missouri
Hope I didn't offend you somehow, I'm just promoting discussion and appreciate the knowledge.
Just the opposite. I tried to remove the message after I wrote it because of your very good reply to it later. I inferred that I knew more about these systems than I really do. I apologize, and I promise to work on that.

I know that full wave rectifiers can improve the power output of sinusoidal power sources that can keep up, but I obviously lack knowledge of 2 cycle mag systems. They might not be able to keep up, and might rob ignition power if they can. So don't mind me. Listen to the smart folks instead...