Generator idea.

crazyman

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All of these engines, no matter who makes it, have a rotating magnet on the flywheel that makes voltage in the coil for the ignition.

An ignition coil wouldn't work for my idea due to the high voltage level. However, any small piece of steel with wire wrapped around it will make AC voltage when it's mounted next to the magnet, somewhere on the shroud or on the block. Turn ratio and wire diameter would take some experimenting to get the volts & amps to where they are needed.

On mower engines, unregulated, they make between 15-22 volts. Just add a simple lawnmower voltage regulator, and you have 12 volts that will power lights.
 
I've been interested in winding a homemade coil as well. The big issue is where and how to mount the thing. May even have to modify the cover.
 
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giles

The things I learn just reading new posts. I have been thinking about a generator for the bike. I already have a small motor that was used to make a doggie door go up and down. Looking at your picture I think you would be better off mounting that little motor to the clutch cover on a small aluminum frame instead of the bike frame. With that in place I just need a USB cable to charge my NiteRider's Battery.
 
The frame mounted generator looks promising.

As far as mounting a coil outside the magneto case goes; do you think the magnetic field would be strong enough, at that distance, to generate any real power?
 
Forget the idea of building your own induction coil,it's a waste of time &effort,the reasons are the following:
1) a piece of soft iron will not do,the eddy currents induced in it by the changing magnetic field will largely neutralize it,leaving little net field intensity to induce a voltage in the winding,so the efficiency will be low,all you do is heat up the piece of iron,a laminated transformer steel armature is required,to keep the core loss down
2) The clearance between the armature and the flywheel magnet has to be quite small in the order of 1/64"or less (0.4 mm) in order to get a strong enough field, necessary to induce a useful voltage without requiring an undue number of turns and excessive resistance in the coil,resulting in low power output and high losses.
 
I can get laminated transformer metal from old transformers that I already have, and use a dremel to cut it to the proper shape.

The coil wire makes a good point. It would take a lot, but if we could get even a small amount of power that's more than the ign wire, than it would be worth it to me.
 
Giles, great idea man! Now I'll share one of mine with the board that I've had in my head for a while.

Nice to know somebody is serious here! How about turning a GMAC car alternator with the back tire off of a homemade mount????
 
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