I have a 79cc predator engine, and I'm looking for a way to get generator power directly from the engine. My goal is to power a 12v electrical system (headlight, tail light, brake light and battery), in the simplest way possible. I know that if I attempt to hook an accessory wire directly to the coil, it will more than likely kill the spark. Now, I have one idea that I've come up with that is fairly simple and inexpensive, but let's set that idea to the side for a minute because I have just come up with another idea that, if a viable option, would be the simplest and least expensive way possible to do this (I hope, anyway). Say i took an ac capacitor, and connected the input wire to one of the coil mounting bolts, and ran the output wire to my rectifier. Would this work? And what voltage capacitor would I need? If this would not work, is there a coil with an accessory wire that could be used in place of the current coil? The only other idea I have come up with is a magnet and coil, mounting the magnet on the end of the crankshaft and fabbing a bracket to hold a coil close enough to the magnet to draw power. The magnet and coil I speak of are available for purchase and will work together, but mounting them in the position I've described is tricky and possibly consuming more space than I am comfortable with. So the capacitor would likely be the cheapest and simplest if it would work, or if not the coil with accessory wire would be the next best bet if anyone knows of a coil that is compatible with the 79cc predator. Can anyone help with this? If anyone hard any better ideas that are simple, cheap and not going to consume a lot of space, I'm all ears.
electrical question for predator engine
I already have a battery and my lights are led. The point is to create a power source to charge my battery. Would you care to explain why neither of my ideas will work? The capacitor idea might or might not have worked, OK. But finding a coil with an accessory wire surely is not a totally bad idea? I'd appreciate an explanation as to why neither idea would work. Simply saying "won't work" is not a good enough answer for me. I'd also like to know what makes you qualified to give that answer.
Look at the specifications for the wattage created by the charging coil (if any) in the engine and at what rpm that value is measured at. Compare that wattage value to the wattage load of the devices you wish to power. Your engine's "generator" needs to make somewhat more wattage than your devices consume due to inefficiency, age, rectifier heating, loss of magnetism strength in the flywheel and losses due to wire resistance, etc. I would derate your device loading by at least 30 % to give your design a comfortable margin.
My guess is that you will find that not much can be powered. My old Honda minibikes had a 62 watt stator at high rpm when they were brand new. The magnets have not gotten more powerful with age and I still need to keep my battery charged. This leaves very little for anything else when I need the headlight, tail light and turn signals. My brake light is the real consumer of power on an old Honda bike.
Rick
My guess is that you will find that not much can be powered. My old Honda minibikes had a 62 watt stator at high rpm when they were brand new. The magnets have not gotten more powerful with age and I still need to keep my battery charged. This leaves very little for anything else when I need the headlight, tail light and turn signals. My brake light is the real consumer of power on an old Honda bike.
Rick
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Have you thought about driving an automotive 12 volt alternator with a pulley from your Predator? You could easily get several hundred watts out of that at 13.8 volts DC that could then be converted to 120 volts AC. The electrical connections to do this are not hard. The bracket and belt tensioner would be the hardest part.
Beyond that, without a charging coil to do lighting on the bike, I agree that it might not be very dependable.
Rick
Beyond that, without a charging coil to do lighting on the bike, I agree that it might not be very dependable.
Rick
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Coil and flywheel. Good luck finding them. Those engines are not desirable at all so they don't waste their time making a lot of aftermarket parts for them. You would be better off buying a 196cc Honda Clone off EBay that has one built in for around $200 shipped to your door. Ones from CarollStream even have starters built in.
I have seen others use belt-driven tractor generators. I am looking for something smaller, simpler and cheaper. I know that something can be done. If you don't think an idea of mine will work, I'd appreciate a technically detailed explanation as to why. I have a Honda generator coil for a gx engine, I know I can fab up a bracket to mount it above the predator flywheel. I also didn't ask the popularity of my engine or the abundance of aftermarket parts, but thank you for your input, however irrelevant.
You don't have a rectifier.
Ohms Law as well as Faradays Law on Induction applies. A review of the electronic components in your engine is in order, as well as the relationship between inductive coils, magnetic polarity, full wave rectifiers, and horsepower to watt ratio.
Every aspect of your "question" violates basic principles of physics.
I suggest you enroll in your local Community College for a Basic Electricity and Electronics course. Then take the next one, and in that course, your questions will be answered.
I certainly don't feel the need to provide the same information to you for free with the type of attitude you are displaying.
Ohms Law as well as Faradays Law on Induction applies. A review of the electronic components in your engine is in order, as well as the relationship between inductive coils, magnetic polarity, full wave rectifiers, and horsepower to watt ratio.
Every aspect of your "question" violates basic principles of physics.
I suggest you enroll in your local Community College for a Basic Electricity and Electronics course. Then take the next one, and in that course, your questions will be answered.
I certainly don't feel the need to provide the same information to you for free with the type of attitude you are displaying.
You keep bumping it to the top every time you respond. Sometimes they leave posts like this up because people get to read your responses. Maybe you should go back and read them to see how you come across. I'm sorry your motor isn't what you hoped it would be. I'm sorry you can't get it to do what you wan't. I'm sorry you wan't to delete it so much because I find it funny every time you ask. Lol