This post shows and explains the design of the eBike I built myself. I decided to post it on this specific forum because this is where it all started, by stumbling on another post, as mentioned in my entry.
This is fantastic, well done! I love the simplicity of the kit.<p>I'm extremely surprised to hear that soldering the XT90s was hard. Even a $20 Pinecil (well, maybe I shouldn't say "even", it's a fantastic iron) can handle those no problem.<p>Also, what cost 1200 EUR? That motor costs 30 EUR, an ESC another 40, and the batteries maybe 80 EUR for Li-Ions (less weight). Were the CNCed plates that expensive?<p>EDIT: Added the praise I meant but realized I forgot to actually write.
A few ideas:<p>* A VESC based ESC instead of the HobbyWing one will give a lot more control and telemetry, including a phone app and detailed current use logging. I know from RC planes that HobbyWing ESCs are very high quality, but VESC is specifically written for drive systems and has a lot of features.<p>* LiIon or LiFePO4 round cells are safer and more energy dense than LiPo pouch cells, at the expense of current sink capacity you don't need. They're also cheaper.
Well done, a very unique design! What made you spec the motor so high?<p>A 2400W motor is very powerful for a bike. For Americans, 750W is one horsepower so that's over 3 HP which should get the bike to ~40mph or 70km/h.
Hey there! Nice work, looks great!
I've built a few of these and the biggest concern with those motors (I've tried them before) is that they aren't made to handle the torque of even small hills. They'll burn out on mile 25. It's not the wattage that's the problem, they just start to slip and burn out unless you gear them down a lot, but then you lose a lot of their speed. Maybe I've just always bought cheap stuff. Also worried about the tension on the chain, is it adjustable?
I also had trouble with XT90 in the past. I would melt them. Proper soldiering iron fixed that.
Nice build! It's super unique!
Nice work. I'm still clinging to my conventional bikes, but anticipate when <i>something</i> will eventually push me over the edge, such as old age or a long distance commute. I've been reading whatever I can learn about e-bike technology so I'm ready.<p>So far the simplest assist I can think of would be a front wheel hub motor and a switch that turns on a constant amount of torque. This would still let me control my speed by how hard I pedal. Of course I'm scratching my head over how I would control it, since it would probably not be an off the shelf controller. But I'm also fascinated by the electronics, and having to design my own controller would be a benefit, not a liability. I also have an obsession with knowing how things work, that I have to contend with.<p>Of course all of this is until I think of something better.
Excellent build, also very beautiful to look at; I hope to see a video of it in action. It's strange that the author encountered difficulties in soldering XT90 connectors; I actually never soldered more than a few of them but never had any problems; it is possible that either they were of dubious quality (far east clones with possibly sub par copper contacts?) or they weren't clean enough. Nothing that a good solder iron, as the author suggest, and good use of flux can't cope with.
For those in need of a good solder iron, avoid cheap no-name ones or Hakko 936 and similar clones and all those using the same stylus (there are at least a dozen different rebrands) because they all are bad: they indeed work with very small solder joints but will fail with bigger contacts or larger pcb tracks, although the power should allow them; the reason is always the same: too small thermal mass and bad thermal contact between the internal heater and the tip. Any used Weller WTCP will perform a lot better roughly for the same price, or check the Pinecil, which for the price performs really well and is also a 100% Open Source Risc-V platform.<p><a href="https://pine64.com/product-category/pinecil/?v=0446c16e2e66" rel="nofollow">https://pine64.com/product-category/pinecil/?v=0446c16e2e66</a><p>About bicycles, unfortunately I'm too big for them; even if I wasn't overweight, my mass would exceed 100Kg anyway, but hope to see 3 wheeled EVs imported or produced in Europe. Someone here mentioned Arcimoto a while ago and now I'm in love with their Roadster model after seeing a video. Unfortunately, high price aside, it's US only at the moment.
Cool build, but it doesn't look like it would actually stand up to the typical stresses of mountain biking (rock strikes, water, mud, debris, etc). On super smooth singletrack I could see it being fun though.
You mention a throttle - I had a skim but couldn't find anything, I wonder if you considered adding a pedal-assist system of some sort?<p>I suppose a throttle is a much more direct connection between your mind and the motor control, unfortunately they are illegal in my country.
Is it weather proof? I guess not since the motor windings are exposed? Where did you get the sheet metal fabricated?<p>Otherwise looks good!<p>When I got a 3D printer it was amazing to be able to make my own designs, but I wish I had the capability to work with more durable materials.
I love that you focused on commodity parts. That is excellent, I really like the placement of the system. Do you intend to take it trails riding? I would just be careful of those XT connectors and be mindful that you've reduced the clearance when traversing over ledges or rocks by moving the lowest point farther forward (you'll hit it quite a bit sooner essentially).<p>I also love that it's internally geared, I've always felt this made way more sense for mountain bikes anyway given the weather protection. Good stuff!
Nice build.<p>I was watching a video of some Russians converting a very old bike using the motor of a washing machine. Very amusing: <a href="https://www.youtube.com/watch?v=dDizHIjZqBM" rel="nofollow">https://www.youtube.com/watch?v=dDizHIjZqBM</a><p>That contraption looks a bit scary of course but it goes to show that building a e-bike is not that hard. Which is I guess why there are so many companies doing that right now.<p>This one is really nice though.<p>I live in a big city (Berlin) and e-bikes are perfect for getting around town. You see a lot of the delivery services using them. Also in a weird bit of investor inception, you see drivers of one VC funded company basically using the e-bikes or scooters of other VC-funded companies.
I would love to understand how the motor works out to adjust its component to torque so its assistive and not replacement. I guess a stage=1 is to make the throttle and the smarts are human (and its PBCK if it doesn't pick up right to conditions) and stage=2 is to move some of the smarts down the foodchain a bit.<p>The high-end E-Bike I rode briefly did a marvellous job of detecting road conditions and maintaining semi-constant speed. The ones I use on the street are more crude, they use pedal effort as a primary guide to intent but back off aggressively, I guess to limit risk to pedestrians. I am pretty sure off-road wouldn't want that. (not a big e-Bike rider, just fascinated)
That's a beautiful piece of work, if I may make a couple of suggestions:<p>- chamfer all exposed 90 degree angles<p>- shrinkwrap the whole thing so it is protected from the weather and dirt<p>- add a connection at the top of the motor frame to the bike to better deal with the reaction forces
What is the max velocity?
I sometimes see people on new fast e-bikes and it seems a bit scary. And sometimes the rider also looks a bit scared or not really in control.
I love the design and build, great job. As a dutch guy i miss splashbacks. You can get some very cheap click ons like these <a href="https://www.bikester.nl/red-cycling-products-universal-spatbord-set-M301955.html?vgid=G338722&cgid=37008" rel="nofollow">https://www.bikester.nl/red-cycling-products-universal-spatb...</a>. It will save you from the black stripes on your back and face.
How are the mounting brackets made (or obtained)? You said you didn’t want to CNC anything, but they look CNC or laser cut?<p>Any estimates of your expected range?
It's a conversion of an existing bike to be electric, right? Or did you design and build the frame, too? Either way, nice work!<p>I think we're about to see a lot of innovation in scooter- and bike-adjacent mobility things - I don't mean the motors, but the frames etc... eg we might see more cargo e-tricycles?
Site is getting hammered and they already scaled up.<p>Very useful site with more similar examples, but just in case you want to save them some bandwidth in load ( it contains multiple images of the bike):<p><a href="https://archive.is/QMx56" rel="nofollow">https://archive.is/QMx56</a>
Curious why there is a derailleur, but seems to be only one fixed gear at the back? Guess you trust that motor to have enough torque to not need any rear gears?
I think you did a great job designing and implementing this. However if you are in Germany unfortunately electric bikes and other personal electric vehicles with a top speed over 15 km/h (off the top of my head) need to be registered with the traffic authority and carry a license plate. It’s basically impossible to do this for DIY builds, as far as I know.
efficiency: not so much<p>noise: quite a bit<p>also bear in mind that just 100w added to someone which is already sportive is quite sufficient for commuting. going harder would put excessive wear on bike chains that for me are already excessively thin.<p>now, tires and brakes. did you use bicyle grade tires that are way too soft or some ebike rated tire that are much harder ? also brake, olease check your brake, you don’t need to be electric for make the brake suffer, so that you need bigger discs, ceramic pads…