I built this electric bike for commuting to work. I stretched the rear triangle section partly because I wanted the extra cargo room and partly because I just liked the look. :-)

Step 1: Cutting and Welding

I started with a few curbside-recycling bikes which I welded together to make a stretched frame. I used a simple jig (made from parts of an old exercise bike) to try to keep things mostly straight ;-)

Step 2: Testing the Hub Motor

This show the initial testing of the hub motor and controller. I'm using a 20Ah 48V LiFePO4 battery, which is not shown in this photo. The hub motor, controller and battery were all purchased on EBAY.

Step 3: Rolling Chassis

Note the 2 kickstands. I need both due to the stretched frame and the battery weight.

Step 4: Final Touches

I'm happy with the performance of the bike. I can sustain 25 MPH with moderate pedaling and I can easily commute the 15 miles (each way) to work and the battery still has reserve charge when I return home. I installed a DC-to-DC converter (from an RC Hobby supplier) to generate 6 Volts to run the headlight and tail-light so all the electrics on the bike run from the 48V battery.
<p>Great work!</p>
Nice work! You mention it's a 48V system; what kind of batteries do you use to get that kind of range on it?
The bike has a 20Ah 48V lithium battery (check EBay). It was expensive, but in my opinion worth it because lithium batteries are much lighter and they last longer than lead-acid batteries. I have never really tested the battery to its limits so I can't say its absolute range and much depends on riding style, terrain, etc.
This instructable doesn't really tell how to do build this. I'm a beginner and this isn't helping on how to mod a bike into an electric bike.
How is the light work? Do you have to press some button every time to have it light up?
The tail light comes on when you turn on the bike main power. The head light comes on when you turn on the headlight. The headlight has flashing and non-flashing modes. Both tail light and head light are powered from the main battery.
ya how much did the hub motor inparticular cost
The hub motor itself was about $100 without the rim or spokes. Adding a good quality rim and spokes and labor to lace the wheel pushes the cost to over $200 for the completed rear wheel.
Our hub motor is much cheaper than your price,if you want to buy next time,you can contact me.
Where can I find hub motor?
You can find them on EBay .. and there are a number of other places where you can buy them online .. try a google search for &quot;hub motor kit&quot; ..
Scd,you can use the water bottle battery or hub batter pack.
Scd,you buy the spoke motor from golden motor?You are very good,you install the e-bike by yourself? <br> We are the manufacturer of the e-bike conversion kit,if you need,you can contact me.
has the frame cracked yet? i can't see how the load could effectively be transferred to the rear wheel.
The frame is strong and shows no signs of cracking
Great instructable, I'm very happy to see how many people are using motorized bicycles to supplement or replace their dependence on cars.<br>I do think that dogbeardbirdbeer has a point, in spite of the gruffness of his comment. Due to the lengthening of the frame, the bicycle is structurally weaker than it was originally. Specifically, the area between the seat post and the rear tire. You might avoid future problems by adding a pair of additional braces. I'd say the most efficient placement would be to divide the rear parallelogram into two triangles. In a line similar to the top/front of the rear tire. Just a thought.
Is that a 1KW motor?<br><br>I've got a kit from eBay, but I'm concerned that it would not be road legal?
It depends what state you live in. <br> <br>In &quot;Florida&quot;, any motorized vehicle needs a license and a plate for a motorcycle. Since there is a second law that states it is illegal to drive any motorized capable vehicle on sidewalks. (Even if you do not use the motor, it is motorized.) Thus, you are left driving on the road, and driving a motorized vehicle on the road requires a license and a tag. The only license and tag allowed on a non-car, is a motorcycle license and motorcycle tag. <br> <br>Thus, any motor is legal, as long as all other road-vehicle requirements are met. (Mirrors, signal lights, breaks with adequate stopping power for the drive-system, helmet, and break-lights.) <br> <br>Most states have similar DOT laws. Few states allow motorized vehicles on sidewalks, and most demand similar requirements for motorized vehicles on the roads. Just because you can't find the laws, or because you haven't been caught yet, or they don't actively enforce them... does not mean they don't exist. Ask your insurance company. That is when laws get actively enforced 100%. On the road, it is a lotto gamble. <br> <br>BTW, Nice setup.
i read if it has pedals on it with chain still attached it is.
if you dont mind me asking. minus the bike how much did all this cost?<br>
The most expensive component was the 20AH LiFePO4 battery at about $400. <br>You can get cheaper batteries at lower AH ratings or lower voltages but the<br>20AH gives good range and is a good fit for this bike.<br>The rear-wheel/hub motor/controller was the next most expensive at about $200.<br>
ouch! thats like a months worth of paychecks for me. lol.
Nice finished product - I can see why it's used as the title thumbnail for 'Electric Bikes'.<br> <br> However, as others have noted, this really needs more (and more detailed ) instructions and insights:<br> <br> What was the design process? - <em>Why</em> did you decide on this design over (any) others? What mistakes did you make - and how did you correct them? Explain to the layman why you put that extra tube behind the seat, down to the bottom forks (strength and support, presumably, but what led to its placement, given its lack in the first picture?) You came close to the sort of thing I'm talking about when you mentioned the 2 kick-stands.<br> <br> Knowing my way around a bike as I do, along with some basics of bracing and welding, I can follow your texts and pictures to create a copy, but others aren't able to do so...<br> <br> And, besides, I don't want to make a copy - I want to be inspired to expand and adapt stuff to my own wants and needs, which is so much easier when someone can warn you of the pitfalls.
u could use a double seater then there would be less welding and cutting
You should put a kickstand on each side and weld them together in an A frame shape like a moped kickstand. Then your back wheel would be off the ground and more stable.<br />
My minibike has an A shaped kickstand. I hate it. I have to lean the bike up on buildings and stuff since that kickstand is terrible. It's great on smooth, perfectly flat pavement, and that's it. Any dirt, any hint of a hill, and the bike goes down. I have a moped that's much taller than that minibike, and I have a side kickstand on it with almost no problems.
Great job. For the clueless, like me, more pics would be awesome. I love the suitcase on back!
Beautiful! Anything special about using a hubmotor with a deraileur shifting mechanism, like you have. Brake issues?<br />
Great job! a few more pics, and some tips as to how to do this step would be helpful for a true novice.<br />
The car is true that we Chinese do not have such a car, do not know what kind of car What's your name.<br /> You can see on my site also has a good car<br /> <a href="http://www.folding-electric-bicycle.com/" rel="nofollow">http://www.folding-electric-bicycle.com/</a>
nice ible it wilnice ible looks really cool
that is a nice bike you made. Man, i'm jealous. Great job!
Something I've found on the electric long bikes I've built, position of the batteries make a world of difference on how the bike handles. If you have a minute check out my bike, I've found this layout to be very transparent to how the bike handles.<br/><a rel="nofollow" href="http://www.evalbum.com/2052">http://www.evalbum.com/2052</a><br/><br/>
It's a good writeup of the finished product - not a very exceptional 'ible on the grounds that a layman would have a very difficult time reproducing your project from what you've provided...but awesome build! I've got a veritable PILE of lipo batteries from ebay, soldered in parallel strings of 3... I could make a 'dumb' pack but it would have no balancing...and aparently lithiums dont like that.
well, they're fine with being unbalanced, until one goes above ~4.5v or one goes under 3.2v... then they swell, the capacity plumets, and eventually catch on fire. It's pretty spectacular to watch actually, but... not fun to have happen! Just get a balancing charger, they're not too expensive. Although a cheap one would likely have a low output meaning long charging times. Anyways, I too would like to see more build info!
Exactly - with regard to that - it's gonna be a highway commuter motorcycle for a 100km round trip - so I need energy density, and I need it done right. Prius packs are starting to catch my attention.

About This Instructable




More by scd:A Simple LED Flashlight Hack (3xAAA to Lithium Battery) USB-Rechargeable Battery Pack for Bicycle Lighting  Recycling a Laptop Battery Pack for Bicycle Lighting 
Add instructable to: