head and running light on a 12 volt system

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I installed a 12v mini-gen and noticed a decrease in engine power, even without hooking up a voltage regulator or battery and lights. It seems that the drag on the magnet is noticeable with no load. I am building a variable regulator/rectifier to charge 8.4v Li-ion battery pack that will run my head, tail, turn and brake lights. I'm also going to add an expansion chamber and speed carb with a billet aluminum intake manifold hoping to get a little more power out of the engine to make up for the extra resistance the mini-gen has created.
Has anyone else noticed this loss in power after installing the mini-gen?
Feed back and suggestions greatly appreciated.
Here's some feedback, the minigen generates 3 watts, which is less than a half of 1 percent of 1 horsepower, aka less than .5%. It certainly doesn't convert drag into electricity at 100% conversion, but even if it was running at 25% mechanical/eletrical efficiency you'd be loosing an amount of hp that only a dynamo could practically detect.

If it's really running lower than 25% conversion I would say ask for your money back for them selling you a hunk of useless s**t.

I use a system of leds which is plenty efficient and a good old fashion sla deep cycle. I was going to do li-ion but cold weather tends to shut down the circuitry as protection to the chemistry, which doesn't behave well in frigid temps.
 
I installed a 12v mini-gen and noticed a decrease in engine power, even without hooking up a voltage regulator or battery and lights. It seems that the drag on the magnet is noticeable with no load.
Well sure you feel a loss of engine power when some of it used to generate electritcy, it don't come from nowhere and you will feel more loss when it is actually powering things.
 
You're implying that if you're not powering something then the electricity builds up in the coil and acts as a lubricant in the air between the coil and mag...

In something like a 3 phase alternator where the feed amperage can be varied to change the output amps then yes, creating a larger magnetic field to power more things can and ultimately will increase drag force, and of course shutting the coil down will leave you with inertial and bearing friction drag.

On these motors with the solid state magnet and a constant resistance pickup coil it wouldn't matter if you're using the power or not, the drag will remain constant.
 
You're implying that if you're not powering something then the electricity builds up in the coil and acts as a lubricant in the air between the coil and mag...

On these motors with the solid state magnet and a constant resistance pickup coil it wouldn't matter if you're using the power or not, the drag will remain constant.
Are you high or just electronically/magetically challenged?
Solid state magnets, air lubricant?

It's magnet inductance. In this case converting mechanical power into electrical power.
The more electrical power you need, the less mechanical motion power you will have left.

In fact this effect of 'inductive drag' is used on E-bikes, it's called Regenerative Braking, you kick on the generators in the hubs to stop you by converting that mechanical power of the spinning wheel into charging the battery, that's how much drag there is.
 
Are you high or just electronically/magetically challenged?
Solid state magnets, air lubricant?

It's magnet inductance. In this case converting mechanical power into electrical power.
The more electrical power you need, the less mechanical motion power you will have left.

In fact this effect of 'inductive drag' is used on E-bikes, it's called Regenerative Braking, you kick on the generators in the hubs to stop you by converting that mechanical power of the spinning wheel into charging the battery, that's how much drag there is.
Well I wasn't high but I had some to drink yes, and I'm not the greatest electrical engineer (screw them its a different department) but how in the world could I have forgotten about back emf (current through the coil allowed to flow will create a drag) but that emf can't possibly be creating much more resistance in torque than the amount of electricity it's generating, after considering loss of course.

I apologize kc I forget my place at times.

I will state that unless that winding is so God awful that it's managing to create drag that could be felt but only generating a few watts then something is wrong. A coil that size just can't steal enough hp to be felt unless it's interfering with the original system somehow or his motor is running at a quarter horsepower, in which case a half of a single percent of 1 hp might actually be noticed.

Believe it or not but air lubricant is a real thing. I use it twice daily to keep my coat shiny.
 
Believe it or not but air lubricant is a real thing. I use it twice daily to keep my coat shiny.
Never tried that air lube, but I love my Windbreaker II, it lets wind pass right through me with virtually no drag Hehehe ;-}

When you are struggling to even hit 25mph the littlest things matter, like even the difference between a stock and NGK spark plug, but you will feel difference in the other direction.
 
Hello, Can the generator be hooked up directly to the battery a 12 volt moped battery to charge it thanks

They can't charge a battery but they can run your headlights and tail light with no problem. You can install a switch on you handlebars to turn them on and of when not using them. The item is called a mini-gen. They have them on eBay for around 20.00.
 
Actually the whole 12v charging system is very easy.

You need charging coil that is NOT grounded at one end. It looks like the one offered by Gasbike is the easiest to modify:

https://www.gasbike.net/collections/magneto-electric-parts/products/12v-generator

See where it's soldered on the top end? Unsolder it and attach an insulated wire and run it outside the case with the other wire. Then attach it to a cheap 4-pin moped/motorcycle rectifier/regulator like this $4 one for a GY6 moped:

https://www.banggood.com/4-Pin-12V-...-125cc-150cc-Moped-Scooter-ATV-p-1134889.html

The two wires off the coil are the yellow wires, and the red goes to the battery + and green to battery - (ground).

IMAG0366.jpg


For a battery you can use a small lead acid. Gel cells that are 12V 4Ah are very popular for alarm system back up and generally cheap. Hell, that's probably overkill and the 1.2Ah battery posted by Stoltzee will probably be enough.

But that's it! Alternator coil, rectifier/regulator, battery, you're good to go! The worst part is finding a connector for the regulator. In that case you can use a different model with a wire pigtail like this one for $9:

https://www.banggood.com/Voltage-Re...-450-2004-2009-5TG-81960-00-00-p-1077720.html

If you use the Yamaha regulator you wire the coil to white and yellow, red to battery +, and black to ground. Add a toggle switch between the battery and regulator and you're done.

Edited to add:

Here's a good candidate. It's your standard single phase 4-wire rectifier/regulator, comes with a pigtail wiring so you can easily connect to it, and best of all, it's cheap!!

https://www.amazon.com/Wingsmoto-Rectifier-Regulator-Voltage-Scooter/dp/B00ZI7U8RK

And finally, if you don't feel like modifying the Gasbike charging coil, you might be able to use a Briggs & Stratton voltage regulator from their old 5 to 9 amp "Tri-Circuit" system that used a 1-wire stator coil.

https://www.ebay.com/itm/VOLTAGE-RE...-B-S-691188-491546-793360-794360/331879044399

Connect the yellow wire to the charging coil wire, and the red wire to your battery/lights. Use the center hole to make sure the regulator is well grounded to the frame. The down side is you're actually throwing away half of the charger's output, but it will work without modifying the coil wiring. It's the difference between a half wave and full wave rectifier.
 
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Hey, this is some great info, I've been looking for some way to wire up a 12v system for a 4 stroke honda gx 50cc.
I'm only finding threads concerning those chinese 66cc hand grenades with those useless white wires, I should know I had about 7 or 8 of them but the gx just goes and goes forever but what to do to light it up when started?
I could fill a large trash can with all the battery lights I've thrown away, seriously I have to have two of each as back ups.
I'd appreciate any help since you seem to know what your talking about.
Thanks for your post, Joe from Natick, MA.
 
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