Saw something cool, thought I'd share.

Discussion in 'Hybrid Bikes & Trikes' started by Agreen, Jan 15, 2017.

  1. Agreen

    Agreen New Member

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    And I didn't get pictures... sorry.

    I was in Brunswick, GA tonight and ran across a guy who rolled up to a gas station in a trike. I stopped and talked with him for a minute, and he showed me his setup, which was a 350w 24v front hub wheel, but his batteries were only 2 little alarm system batteries tucked inside of small plastic ammo cans. The kicker was that he had a 1000w generator tucked behind the seat tube. It was quiet, and didn't make any offensive noises, ran at a reasonable speed, and just looked really cool to ride on.

    He kept saying something about having an inverter to make the 115vac generator power the battery... Now, he sounded like he knew what he was saying up to that point. An inverter makes DC into AC. A rectifier converts AC to DC. I was curious how he made it all work, especially the rectifier and regulator portion. I didn't want to keep him forever, plus it seemed like it worked, so I won't step on toes for technical terminology mistakes!

    Also, he had a little puppy. Her name is Pie, which I didn't get at first. It hit me on the long drive back to SC. (P=IE) It's the DC power equation. How cool is that?!
     
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  2. CRP

    CRP Member

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    My kids have a Razor electric bike and I could use all those parts to make what your talking about. Just a matter of a adding a small generator which is more a matter of where to mount it? Sounds like a cool project but not real hard to do. I think all you would have to do is use a 24V charger and just plug it into the generator. The charger would regulate the current for you? If not you would have to do the math to come up with a system so you didn't fry the batteries. For that matter all the parts are available for a 36V system as well. He used gel cells like for a UPS? 4 of those batteries in series would get you to 48V. You would be able to put a pretty big electric motor on with 48V.

    Going to have to think about. Just for fun I might figure out how he did it.
     
  3. Agreen

    Agreen New Member

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    My kids have a Razor moped scooter. It runs on 24v too.

    The batteries he used aren't even big enough for an UPS unit. I have 2 of those, and they're relatively large compared to these. They're more like the size of the batteries in a house alarm system.

    I guess it could just be a 24v charger since the generator makes 115vAC, but it was housed in what appeared to be a metal box with factory sealed wires coming out. I'm not sure whwee the unit came from, but he did say it "transformed" (again, wrong term but whatever) the 115 to 24vDC.

    It's not hard to figure out what he did, I had just never seen it before in person. I mean, it was just a little cheap 24v front hub kit, a couple of batteries, a generator, and whatever charger it was. The hard part was figuring out where he sourced his supplies from. He looked kind of homeless, but he sure knew what he was doing. Maybe he just looked like **** that day?
     
  4. cannonball2

    cannonball2 Active Member

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    Down my way. I used to live in Brunswick now live in Darien

    Based on what you have said was the "generator" really an inverter. They are engine powered but are much quieter as they turn less rpms. I cant imagine needing an inverter in addition to a generator when you can just plug in a 115v/24,36, or 48v charger directly to the gen.

    The problem comes with the 1000w output. Its capable of just over 8amps at 1000w constant. Most 24v controllers will pull up to 17amps(350w@24v is 14.5amps). Not sure of the losses thru the charger. However most ebike SLA chargers generally to max at 5amps. So the only time the gen/charger can stay with the motor is when using below 5amps.
    This is the old cant get any more out than you put in, mostly less considering the loses.

    The gen may extend the range a bit especially here in the flats if the trike can ease along at or below the max output. And of course charging while taking a break would work.

    It would still be more efficient to drive the trike directly by the gens gas engine.

    I think I have thought this out correctly. Correct me where I may be wrong.

    BTW was this trike green and did the guy have a pony tail?
     
  5. ragdolldude

    ragdolldude Member

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    I saw a video a few years back about a trike a handicapped guy had. He got a ready made 3 wheeler, mounted a small Honda generator, spoke to a boat company about a charger (don't recall why) and it was an electric drive. If you did some searching on Google or Youtube you should be able to find it. If I recall correctly, he mounted the motor above his "head level" at the rear of the bike.
     
  6. Kartooo

    Kartooo Member

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    don't understand the workings, me and electricity don't get along...
    guess his trike was similar to a train.
    got a friend that works for the local RR that's given me some some nice tours of the train guts.
    big old diesel engine turning a generator that powers the electric mtr to make the train go !!
     
  7. cannonball2

    cannonball2 Active Member

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    Its kinda along the same lines as a diesel electric. Basically the D/E is using the electric motors as a form of transmission.

    This could be made to work very well if a 5hp motor was coupled to a 24v automotive style alternator of say 80-100amps. I did this with an 80amp 12v Delco alternator to run lights in our pits at the night time kart races. Had 12v galore for any need. Was a compact unit too as the alternator mounted directly to the engine. Don't know if SLAs would be the proper battery. Maybe a smaller 24v battery lead acid battery. Something like 2) 350cca lawn mower batteries would probably do also.

    Probably need a purpose build trike though. Saw a big scratch built Etrike over at Endless Sphere that would be perfect.
     
  8. Agreen

    Agreen New Member

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    You're absolutely right about the losses. Maybe a little off with the amp calculations though. You have to consider that the single phase AC power equation isn't just P=IV, it's P=IV (pf). Now, it all depends on the load as to what the power factor will be of the generator, but you can usually assume about 0.8 for the pf if the load is inductive (which the charger should be). So rearrange the equation to I=P/(v*pf) and it comes out to over 10A. I know, it's splitting hairs, and is still insufficient. Even then, as you already said, there's losses involved too. It obviously won't ride forever, but it may extend the range long enough for his purpose I guess.

    Darien isn't far from there. He was right off exit 38 at the sunoco. He sure couldn't have lived far from there with the size of those little batteries! If you ever see him I recommend stopping for a minute to talk. He was real friendly and probably would have stayed and chatted for much longer.
     
  9. Dan

    Dan Staff
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    Very cool, Agreen. I have been wanting to do just that for years. (Bummer about pics. I do that too. Forget)

    But like ya said Cannonball, useing it as a tranny of sorts. Like a train. That would be so cool.

    I have been talked out of it but wanted to take a lil HF gen and a motor. Bam. ( I thought) but sharper folks said its not terribly efficient. Might try any way. Just seems like a cool and easy setup.
     

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