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I want to put an electric motor on a 4-wheel bike- (beach bar cruiser) i`ve got ideas but could always use more!?

I own a surrey(4-wheel bike) that seats six and i want to put an electric motor on it.I am on a really limited budget so i need to do this as cheap as possible. I need to get enough power behind this thing to run about 2 miles and it doesnt have to go fast either- if i can get it to top out at like 5-10 mph that`d be excellent. I was thinking i might use a washing machine motor(approx. 115 volt AC // 10amp) with 1 or 2 12V deep-cycle batteries and a 12V-120V AC/DC inverter. I`m no electrical engineer so i could you guys`s input/advice/opinion on whether i`m heading in the right direction and if this has any potential at all. I`m staying away from a gas-powered motor because i think the cops in my town will pull me over if they see/hear a gas engine on a 4-wheel bike. The real goal here is to get me & my friends to the bar and back without pedaling our asses off. Any advice would be greatly appreciated-

ex924 years ago
hey would it be better if you instaled a motor but some how kept the peddles for back up?
robjabski5 years ago
I kinda have the same problem I'm converting a an toy jeep into an electric Go Kart. I'm looking into a replacement winch motor to drive it, there designed to provide lots of torque and run for long intervals. If you install a couple of deep cycle batteries it will extend you life, but it's not cheap.
timnandy (author) 5 years ago
I found something on E-bay. It`s a 36v DC motor kit w/ batteries , controller, charger. I think this might be just the thing. To any1 reading this- could u search (Ebay / 36v motor kit) and tell me if that kit will be as powerful as it sounds? It looks too good to be true, and could use some reassurance before i drop $100 on this thing.
timnandy (author) 5 years ago
ok- i hear ya about the possibility of the DUI- i`m prepared & ready to accept that. I`ve got 2 friends who are attournys and i know most of the cops in my town. That being said- this is too great of an idea and im going to do it anyway. I`ve been looking at DC motors and for anything above 1 hp they`re kinda expensive but i`m willing to shell out a few bucks- any1 know where i can get a used/rebuilt/cheaper one? i`m thinkin i might need 2-3 hp. I am also planning to use a sprocket and chain to link right onto the existing bike wheel sprocket- that way i can adjust the sprocket attached to the motor shaft to change the ratio, if needed. Next question is - Can i use a light dimmer switch to control the acceleration? And also- if i can find a 2-3 hp DC motor how many deep-cycle batteries will i need to run it? I`ll be checkin this page daily so i can keep on top of any info u guys provide-- Thanks in advance!
Cute idea. The best I can say on the motor is try it. I have a funny feeling it won't create enough power to drive you with 6 riders. You're going to have to figure out how you're going to actually drive the bike with the motor. Will it have a gear attached and mesh with the existing chain? Will it replace the pedals or will they remain? Will it directly drive a wheel? The answer to these questions depends on torque. But honestly, a powered cycle that seats 6... probably would be defined as a car in most places with north american or european-style road laws. You'll probably get in trouble whether the motor is gas or electric.
It would need registration in 'most' places in North America. Also of note, and this is REALLY REALLY important. A bicycle, on a road is considered a MOTOR VEHICLE. you can get a DUI for riding a bike drunk. You would still need a DD to operate this new (and arguably AWESOME vehicle). Onwards: You probably want to use a DC motor, for simplicity. A speed controller can be purchased relatively cheap (compared to an inverter). Then it would run off batteries, without too much hassle.
Also: To interface with the back axle, you'd want another slip-ratchet hub on the axle, and a sprocket/chain or pulley/belt *(chain is more efficient) to the motor. Would likely need some welding done, to keep it strong.
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