I have a 98cc minibike (4 stroke) engine. I don't know if its possible to get power from the engine at all or not, but I would like to be able to charge my batteries on the bike. I have four 7.2v nicads, two in series for my headlight and two in series for my brake light. If I could find a way to charge them on the bike, that would be great. I have 26" wheels, and my top speed is somewhere around 32mph. I was thinking maybe a bottle generator if there is one that won't fry from the speeds I go, or maybe someone could give me some advice on building something diy? Just please don't recommend something like a dynamo hub, or the kubota generator, as I don't have that kind of cash right now. Its got to be inexpensive and able to hold up to the engine speeds. Thanks.
Easy/cheap generator for charging batteries?
- Thread starter bigbutterbean
- Start date
IMHO that means you need to build it yourself via repurposing a small electric motor. Good luck plays a factor, too!
I've used about a dozen bottle gennies since the 80's, and while I have never actually broken (read: fried) one itself, the often-flimsy bracket attachments can give away at higher speed and vibration levels - especially when using the 12v bottles. From my experience, one is pushing em when going over 25MPH constantly. They can get really warm, especially if you running one without any cap whatsoever. They really don't like 35+, I've even pushed em to 40 downhill with pedal bikes years ago
I could wire the proper circuit to the bottle genny, that's not a poblem. They have a nice one on Amazon for like $35, Prime eligible. Looks sturdy and has a lever to disengage it from the tire. I would replace the mounting hardware with grade 8 bolts and nylock nuts. It might be a little while till I have the money, but if I'm not going to fry it, I think that's the way I'll go. I'll post a new thread for wiring the circuit once I pick it up.
Get yourself a 24 v scooter motor and run it at 1/2 engine speed for 12 volts.
Both of my bikes use that set-up w/ no battery, voltage goes up past 12v but no problem -mopeds essentially do the same thing.
All Electronics co. usually has them and cheap.
Make sure you connect the polarity correctly and have a disconnect switch for when the gas engine is not running.
Both of my bikes use that set-up w/ no battery, voltage goes up past 12v but no problem -mopeds essentially do the same thing.
All Electronics co. usually has them and cheap.
Make sure you connect the polarity correctly and have a disconnect switch for when the gas engine is not running.
I think a scooter motor is more trouble than its worth. I can't even tell if my engine will produce enough juice to power the darn thing. I have a multimeter, but the readings confused me. I put the positive lead to the ignition and the negative lead to ground, and got 4.5v or so. Put the negative lead to ignition and the positive to ground, 8.4v. I don't really want to figure out where to put the motor, then have an on-off switch and all these things. The 12v bottle genny should work fine with a cap and a regulator. I will build a circuit and find something to encase it in, such as a project box from the Shack or similar. The circuit can be hidden away in my saddlebag, and the bottle genny will be hidden from view by my saddlebags as well.
bbb, have I got a deal for you! If you are feeling creative, have some free time to surf the web for whatever information there might be, don't mind stuff coming in bits and pieces, then I can send a bunch of stuff your way for the cost of shipping. If you want it I have a bottle generator and a minigen regulator (the eBay thingy). Both have been tinkered with.
I tried and gave up (reworking the lights thread in the Cruisers forum) and have gone with the Kubota. Actually, I saved a lot by not getting a Kabota and getting a Cub. Same alternator. I will be using this with a used Yamaha rectifier which was also a cheap eBay score. I'm driving the alternator offhe jack shaft.
Shoot me a PM if you want the bottle generator and we can work something out.
I tried and gave up (reworking the lights thread in the Cruisers forum) and have gone with the Kubota. Actually, I saved a lot by not getting a Kabota and getting a Cub. Same alternator. I will be using this with a used Yamaha rectifier which was also a cheap eBay score. I'm driving the alternator offhe jack shaft.
Shoot me a PM if you want the bottle generator and we can work something out.
PM reply sent!
My mistake on the alternator. It is a Deere not a Cub. I paid $50 and like the Kubota it is a matter of constant searching of the listing and waiting for a good used one. The new/refurbished ones are $119.
My mistake on the alternator. It is a Deere not a Cub. I paid $50 and like the Kubota it is a matter of constant searching of the listing and waiting for a good used one. The new/refurbished ones are $119.
Supposedly 12v. Never had it on the road since I installed it in the winter. Like I mentioned in my PM, give it a whirl and if it works for you great and if not then, I dunno. It's going to be yours either way and if you can cover shipping that'd be nice. If it doesn't work for you, pass it on to someone that can use it and keep the shipping (or buy somebody a cup of coffee that needs one).
It should work out fine for me since its 12v. I'm also pretty sure that someone here can help me figure out how to wire it up. I'll get back to you on the shipping as soon as I can.
Took a few days to dig through all the "treasures" in my garage but I managed to track down the loose parts. Should ship tomorrow. Don't worry about the shipping.
I should definitely be able to make the generator work. My wife's brother in law just gave me a positive power splitter with 5 connections. Coincidentally, enough for the generator, both batteries and both lights. All I need to do is figure out what regulator and rectifier to install.
The correct term for the part is a power distribution block. Its got one in and 4 outs, but I tested it with a battery and a light bulb, and power can be drawn from any of the poles. The generator will be connected to the "in" connection, and each of my lights and batteries will be connected the the 4 "out" connections (two batteries and two lights). This way, the lights can be powered by just the batteries, or the generator and batteries at the same time. The lights can each take up to 30vdc. My plan is to install a 16v switching mode regulator and a rectifier that can handle up to 50v with thermal shutdown (I may still have one that works, have to look through my parts). Once the generator is installed, I plan to run my lights all the time so as not to over-charge my batteries.
Hope it works for you. This is what's on the way as far as the generator: http://www.ebay.com/itm/Classic-Bic...828?pt=LH_DefaultDomain_0&hash=item20ae043924
And this too:
http://www.ebay.com/itm/12-Volt-Min...072?pt=LH_DefaultDomain_0&hash=item5d2856fd28
And this too:
http://www.ebay.com/itm/12-Volt-Min...072?pt=LH_DefaultDomain_0&hash=item5d2856fd28
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