49cc generator

The white wire on the 2-stroke only produces about 6v 3 watts average (0.5 amps). It can spike much higher, but it's been long known that if you draw too much from it, then your engine may not run. Best to keep white capped IMHO. There's a couple of guys on eBay that sell regulated 6v and 12v retrofit kits for use on the chinagirl motors, but I cannot opine on how well they work and haven't seen much here about em.

Basically, if you want real light without plug-in recharging, you have to build your own genny. I'm still a n00b at that myself and hope someone comes forth to explain it laymans terms too lol :D
 
How to Build a Bicycle Generator Difficulty:Moderately Challenging. Things You'll Need: Bicycle, Soldering iron and solder DC Motor, Battery, or appliance to run. Instructions: Acquire a DC motor from somewhere. This can be from an old printer or computer. Motors are in almost everything. You could even go buy one from Radio Shack if you were so inclined. Take all plastic gears and o-rings off of the motor. Mount the DC motor onto the back tire so that the tire turns the shaft of the motor. You might need to put on some sort of disc to the motor arm so that it touches the tire. I have used big rubber discs in the past to get good friction. The turning causes a voltage to come across the leads on the motor. Use a voltmeter or multimeter to measure the voltage coming out of the motor when you are pedaling. There will be enough to charge a 12 volt battery, or power a small TV. Attach a voltage regulator from the leads of the motor to whatever you will be charging or running. Without the regulator, the batteries can explode. Voltage regulators are small chips that can simply be soldered onto the circuit. You can get a schematic for each voltage regulator. You can get them online ar at an electronics store. From the voltage regulator, you can go straight to batteries or the appliance you are running. Expect to get about 100 to 200 watts of power if you are using the right motor. Obviously, if you are charging batteries, use rechargeable Nickel Cadmium or Lithium Ion batteries.If you are building the generator on a moving bicycle and not a stationary one, just mount the battery holder somewhere near the back tire. I like to mount mine above the tire right next to the motor so the wires connecting it are short. Make sure that they are tight so they don't get caught up in the tire. Don't get frustrated if it doesn't work the first time. Electronics is about learning and no one is perfect. Eventually it will work.You can also attach our generator to some high powered LEDs for riding at night or to power a radio to listen to music while your cruisin.
 
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These aren't my instructions, but I thought they might come in handy. I can't really answer any questions at this point because I haven't attempted to build this generator yet. But if you do it right, it would work exactly the same as any bicycle generator, maybe even better.
 
Hi, here's a quick update on my progress. I got a few quotes for machining the mounting hardware and for the 10 alternators I will use as testers, the cost per unit is really high (over $90) so I am definitely hand making the first batch. I had to order more material and tools but once I get them I'll start production.
 
ok, so i have a 12v sealed lead acid battery and a 12v motor. the motor is a starter motor used to start gas powered r/c cars and planes. if anyone wants to google it, its a hobbico torqmaster 90. i want to mount the motor so it can be driven by the rear tire, and use it to charge the battery, then use the battery to power a 12v halogen light to use for a headlight. any thoughts or advice on this would be appreciated.
 
Can't say in your case, but the one's I've tried seem to generate about half the voltage they run at if the rpm are the same. I used a 24 volt scooter motor to get about 13.5 volts.
 
interesting, and how do you drive the motor? is it driven by your rear tire, as mine will be, if so, what do you attach to the motor arm to drive the motor? perhaps the size of the drive disk has something to do with the rpms and voltage. im not sure which way it works, but i know different size drives will give different rpms the part im unsure about is whether a smaller drive disk will give higher rpms, or a larger drive will give higher ones.
 
bigbutterbean said:
interesting, and how do you drive the motor? is it driven by your rear tire, as mine will be, if so, what do you attach to the motor arm to drive the motor? perhaps the size of the drive disk has something to do with the rpms and voltage. im not sure which way it works, but i know different size drives will give different rpms the part im unsure about is whether a smaller drive disk will give higher rpms, or a larger drive will give higher ones.
Click to expand...

Sorry to get you excited. I didn't mount it, I was just experimenting. I tried various PM motors driving them with a drill press with a tach on it. I used everything from 12 volt motors to a 120 volt dc motor. At their rated rpm's they usually produced about half of what they needed to run.

I even tried a hubmotor with regen braking to charge the battery. It worked, but the output gained for the extra drag wasn't acceptable to me. I'm still using batteries (sla and 12 volt makita lithium ion) to power the lights. My next build is using a Lifan monkeybike engine with electric start and charging, so that will be one less problem to solve.....I hope. :>)

By the way, a smaller disc will give more rpm's and higher voltage. Just like a friction drive in reverse. I was planning on using cut down skateboard wheels.
 
Another tidbit of info that might help you.....the scooter motors I tried were the Unite type. Depending on the manufacturer, they will run them at 24 or 36 volts with the same motor, so that might give you a few ideas as far as what to try. Your motor probably has some specs on it....like 12 volts will give x rpm's. It will probably produce about half that driven at the same rpm's. The power consumed goes up drastically the faster you try to overdrive it. The 120 volt motor produced about 58-59 volts at about 5600 rpm's. I was using that to recharge a 48 volt battery bank for a hub motor.
 
It seems to me that this thread is getting seriously highjacked, making it difficult to follow. If you want a side discussion about your idea or approach that involves a number of posts, then start your own thread. A little respect goes a long way here. Just my opinion.
SB
 
I Agree this is about stators and coil to make power no moving parts.......
nothing rubbing on tires That is so OLD shcool ..Yes please start you own thread..
I hate to be hipacrital as i also mentioned 3 phase motots way earlyer in the thread
befor I new what this was actually about...I think IT'S all A's thread now...
 
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disregard my last post Butter you go buddy any info is good info..It's the creativity thats important. When you post anything you get people thinking . If it's a good idea people will take it and run with it in all differnt directions. Some are successfull some aren't . But you'll never know if you don't try. But anybody can start a thread if it's a good subject you'll see it take off. THIS IS SUPPOSE TO BE FUN. Sorry....Flex..
 
Orvil,Wilber you need to stop wasting time ,if men were ment to fly god would have given them wings.
lol
 
That would be Orville, Wilbur, and wdbtchr. I've wiled away many hours and still don't have it right.

Still can't wait to see what A ends up with. One of my bikes could use that.
 
A good bit off topic and please forgive me. But, a really cool and important thing to us an' this, the greatest thing the Write Bros came up with wasn't the plane. It was the way to test before the dumber brother went up. (Trust me. I was lil bro and a whole lot slower, lol)

1901 Wind Tunnel
 
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