Electric vehicles are getting more traction these days, but this trend is rolling towards us in more ways than just passenger vehicles. More and more bikes are being electrified too, since the cost of batteries has come down and people realize that they can get around town easily without having to pay the exorbitant price to own, fuel, and maintain a car. Of course there are turnkey ebikes, but those don’t interest us much around here. This ebike from [Andy] is a master class in how to build your own ebike.
Due to some health issues, [Andy] needed a little bit of assistance from an electric motor on his bike, but found out that the one he wanted wouldn’t fit his current bike quite right. He bought a frame from eBay with the right dimensions and assembled the bike from scratch. Not only that, but when it was time to put the battery together he sourced individual 18650 cells and built a custom battery for the bike. His build goes into great detail on how to do all of these things, so even if you need a lithium battery for another project this build might be worth a read.
If you’ve never been on an electric bike before, they’re a lot of fun to ride. They’re also extremely economical, and a good project too if you’re looking for an excuse to go buy a kit and get to work. You can get creative with the drivetrain too if you’d like to do something out of the box, such as this bike that was powered by AA batteries and a supercapacitor.
21 thoughts on “Electric Bike From The Ground Up”
I like the idea of an electric bike – I’m lazy and don’t care much for peddling too hard. I used to ride to work every day till I moved further away and started driving now I e got used to been warm and dry getting back on the bike is now so much more difficult. I need a fully enclosed recumbent with air con now lol
I can SO relate to this. I used to ride 11mi round trip to work, now I work from home, no commute needed. But now I live in the PNW. A fairing will be desired! See my link in my comment below to see what I used to ride to work. Hint: 9 feet long and recumbent :p
My winter project is going to be a long wheelbase recumbent. It just might get electrified! I built one 10 years ago, it was not electric though. This one will be like it, but shorter. Details at http://miscdotgeek.com/diy-recumbent-bicycle-build/
Oh damn ANOTHER project I’ve just GOT to do !!
Right!? Follow my blog if you like, check my youtube channel (miscdotgeek) I’ll be posting updates there, and hope to build the whole thing on youtube :)
Wow! your Youtube channel is amazing. It’s really worth following and watching. Kudos for your great videos.
I used to ride to work every day too. Up a very steep hill. Steep enough that going down it was scary. After a few years I got a 50cc 2 cycle gas scooter. My old bike had some electronics on it. I had a couple 12V 9AH gel cells and a very bright car headlight and taillight, and a car stereo and a car horn, complete with relay. At night you had no idea what it was coming at you, but it was bright enough that cars gave it some respect.
A nice start! Next step https://www.biblio.com/book/tom-swift-his-electric-runabout-speediest/d/1123891512?aid=frg&utm_source=google&utm_medium=product&utm_campaign=feed-details&gclid=CjwKCAjwqarbBRBtEiwArlfEIDYpXitCL9sID1dADNglAmUAdofHd6dbZHb2R8REiCIUrejYrzKZmRoCOFUQAvD_BwE
This type of electric conversion is ideal as the wattage usage to output can be more efficiently controlled by the cyclist… this is due to the bottom-bracket motor (Probably a bafung? if I got the brand spelling right).
I’ve currently got a 1Kw motor at 48v-nominal, this is plenty enough for the cycle routes here… however a tad slow for the roads… like having a 30cc moped.
Also, back to efficiency… I’ve weakened the magnets a bit over about a years use and the battery has taken a hit as it seems to only store about 80% of the capacity now. This is why I’d be saving up for a 1Kw+ bottom bracket.
that is 4 times the legal unlicensed wattage limit here in the UK.
P.s. the 250W legal limit here in the UK must have been a joke by some politician…. My first e-bike attempt was a 250W+lead acid batteries…. it was harder work than just straight pedaling on a normal bike, Li-ion has made 250W just about usable. The USA has a 750W limit if I recall correctly.
Legal limit is exemption from mandatory insurance for motor driven vehicule.
So you can break it and slap a sticker on it nobody cares. In case of accident it will just mean you ride without insurance..
I have been selling batteries for e-bikes in the past. One reliable solution is conv-e if you do not want to do it all yourself. Have a look. .I know them for many years, and there might be partial options and other products to build e-Bikes.
Now he needs to combine it with the regenerative braking project mentioned earlier to capture some energy from going downhill…
Thats not possible on this configuration, because the wheel can’t drive the motor. The wheel can’t drive the chain
Unfortunately all and every single e-bike project falls into one of two categories: DIY/cheap/weak or Professional/expensive/overkill .
You know this because?
I have both and the one I use is the one I made despite one costing £120 off ebay for all the bits and the other costing around £800..
I think there’s a grey area, but the sad truth is that any ebike that’s enjoyable to ride on the road is expensive.
Any nice bike you see for “sub $1k” tends to have more time invested than the owner likes to admit and often excludes the cost of the bike, upgraded kevlar tires, etc.
I ride my ebike ~100 days a year and enjoy it, but to be honest it would make more financial sense and be safer to drive a gas moped…if it wasn’t for the noise. Starting that at 5am and my neighbours would kill me.
my brother has an old 2 stroke zuma and its very very quiet especially when you consider its a 2 stroke. he’ll show up and I wont even have heard him come up the road.
Point of reference, Andy’s project ended up costing multiple thousands of dollars and not so insignificant amount of time invested.
I’m just here for the “how to design, spec and build an e bike battery” :) the most expensive part of any Bafang or any motor based pedelec solution.
“From the ground up”
That title takes me back to the lead v. lithium recycling article from a few weeks ago…
Ground up batteries an all.
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