gas/elec 3speed motorbike w/ pics
- Thread starter ne2rk
- Start date
Its a old school 3 speed grandma bicycle. It had sweeped handlebars. I cut the seat stay's. I bent the frame's top tube and bent it down, then bent top tube again. and clamped the built in seat clamp back to the seat pole. I owned this bicycle for over 7 years. As one of my many pedal choppers. This bike seemed best fit for my gas/elec beacuse of the 3speed hub. The motor is a 47-49cc raw china slant jug 2stroke. and electric motor is a scooter 240watt 24volt dc motor. chain drivin.
I only rode it one time with the gas motor's chain link snaping twice from rubbin on the frame. need to install a chain tensor. Wish i had a better frame then this. but its fun being that low and under the fender. It has a springer seat. This bike looks cool if you ask me. looks old. rides strait as a arrow. tires hold over 80psi.
only problem is when the battery's go dead i can't get the gas motor started. no pedals....yet...
This bike will be 100percent in the next few weeks. I can't wait.
The simplest gas/electric hybrids use the electric motor only during acceleration. Lexus makes a hybrid SUV that uses that concept to get highway gas mileage in the city. You get better gas mileage, can use smaller batteries and it's mechanically far simpler (and cheaper) than a full hybrid (Prius).
It would be good to use the electric around the neighbourhood so no one notices you, then fire up the piston engine when you need it.
Ive rode it for first time today. I used the electric in 1st gear to get it going around 5mph and pop the clutch to start the gas on choke. roll till down my street till it warmed up. remove choke and engage the clutch lever and give it gas. get it going to around 25mph, then kill gas and lock the clutch lever. pop it in 2nd or 3rd aka overdrive. and fly down the street, silent as the chain allows me to be. I only have 4 12volt 7amp hour battery's at 24volt. So electric isn't the best. till i figure out how to make it regenerative power.
Im thinking ill make it a dresser. Saddlebags from old leather laptop bags from thift store. Those can store the battery's. and a 1 1/8th bicycle stem and bull horn 10speed handle bars for foot pegs. Picture soon...
Good work.
Have you considered power tool batteries? Makita make a 24v pack. Two in parallel maybe. 1 hour charge, tough and cheap[ish].
Is your electric motor running through the gears? It looks like it is. If so, how does it feel? Is there an advantage over a single ratio?
Have you considered power tool batteries? Makita make a 24v pack. Two in parallel maybe. 1 hour charge, tough and cheap[ish].
Is your electric motor running through the gears? It looks like it is. If so, how does it feel? Is there an advantage over a single ratio?
I got 12volt 7ah battery's in series for the 24volt I got 8 of these to mess around with rite now. And alum for a battery box. I charge them with a trickle charger over night. I normally put 4 in bookbag or in saddlebags for the electric.
off subject of this bike. My other electric 3speed bike i put 6 7ah batterys and had a blast for over a hour. up and down hill. up-shifting and down shifting. It pulls/gains speed uphill in first. and flys downhill in 2nd. 3rd will slowly gain speed, it gets kinda scary feeling because the chain and motor gets quiet and the tires start screaming. i only got it going 27mph for around 6miles. but I love these 3speed hubs, id say they have a advantage over single ratio. Second gear feels like normal ratio.
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Thanks for the info ne2rk, I'm looking forward to trying it out for myself. I have a seven speed manual and a 4 speed automatic hub to test when I find a motor.
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My motor's all came from stand up electric scooters from my local battery place E-scrap. they where doomed for the garbage. i also get them from scrapers.
I wish i owned a seven speed. Ive laced a few of these hubs to 20inch double wall rims for my bmx bike.
But on my electric bike. I have to let go of the gas for it to shift gears. Its weird. But i like it. I love when these hubs slam gears. It kicks hard. and down shifting is amazing. These hubs put de-railers to shame.
Couldn't you in theory have the electric motor engaged while the gas engine is running and powering the bike. This would then turn the motor into a dynamo and charge the batteries. it could also be used to charge the batteries on a down hill or for "regen" braking. Thus making it a super simple hybrid.
It would be easy to run them both together and use the electric motor as a regenerative brake with variable draw so you had some control over the resistance, but I dont know if you could get a charger to run on such a low current and get useful boost. It may extend your range slightly but the complications of setting it up might be make it barely worth while.
On saying that, every little bit helps. Maybe it could work!
On saying that, every little bit helps. Maybe it could work!
The 3speed is freewheeled. So no re-gen power from that. I heard any dc electric brush motor can be turned into a alternator. That will be on one of my next bikes. I wish the gas side was freewheeled. Because this raw 2stroke motor dosen't like to down whine. it sounds really chunky. I need to read up on these motor's for maintenance on the motor so i don't blow it up. for some reason this gas motor is only smooth when gaining speed. im still learning as i go along.
Ive rode this bike for last few days and its amazing. I can't explain how fun this thing is. I run that electric in first gear, put it on choke, pop the clutch, let it warm up. I lock the clutch lever so its in neutral. And let it warm up while i use the electric, remove the choke, and pop that clutch and fly down the street with the gas. I then kill the gas motor and pop the electric side 3speed into 3rd gear. and coast down the street till i need to gain speed. Then i pop the clutch and run the gas for few mins and over and over. I spend over 40percent of the time only electric. BUT, When i hit the gas and electric at the same time... Its a champ. Takes off like a dream. flawless. Best of both worlds. video really really really soon... pictures can't explain.
important
I've heard on these threads to "not"let a 2 cycle motor-clutch be engaged when slowing down or coasting down hill w/the throttle closed,,they say it dosent get enough fuel-oil mix to properly lube the motor,squeeze the clutch ,don't just close the throttle,the oil in the gas lubes the motor bearings and cylinder walls
I've heard on these threads to "not"let a 2 cycle motor-clutch be engaged when slowing down or coasting down hill w/the throttle closed,,they say it dosent get enough fuel-oil mix to properly lube the motor,squeeze the clutch ,don't just close the throttle,the oil in the gas lubes the motor bearings and cylinder walls
Haven't updated in 2 years! I ride this motorbike every once and a while. Just last week i welded a kick stand/frame stand on it so i can start it without pushing it down the street.
I took a 15mile ride on it few months ago. While riding i was forced over some potholes and random curbs and did some random damage the hole time. Besides that it was smooth riding.
I got two flats a mile away from home. I had patch's and pump but i just rode home on that rear flat and replaced the rear rim later. Front has slow leak and bubble in tire. rear blew out. I slammed a few bumps and knocked some spokes out in front rim and got a flat spot on the rear rim. I replaced all that. I ran my gps the hole time. Maxed out at 32mph with normal speed 28mph. Average speed was 17mph-23mph.
A few pictures of the rear gear's.
I took a 15mile ride on it few months ago. While riding i was forced over some potholes and random curbs and did some random damage the hole time. Besides that it was smooth riding.
I got two flats a mile away from home. I had patch's and pump but i just rode home on that rear flat and replaced the rear rim later. Front has slow leak and bubble in tire. rear blew out. I slammed a few bumps and knocked some spokes out in front rim and got a flat spot on the rear rim. I replaced all that. I ran my gps the hole time. Maxed out at 32mph with normal speed 28mph. Average speed was 17mph-23mph.
A few pictures of the rear gear's.