Electric Roadster

[Dui ni shuo de dui]

Hello Everyone,

Yesterday I was lucky enough to score an old electric motorbike for free.
It is almost exactly the same as my sports bike, but all the plastic parts on this one are broken. The plan for this one will be to make it a lightweight roadster.

The bike was stored outside for several years without being used, so it is in quite poor condition, lots of rust, corroded brake calipers, many broken parts, paint projections everywhere on the anodized parts, extremely dirty...

Just arrived in its new home:




The controller is a 100A Yuyangking, so that will go straight to the garbage it should never have left in the first place. Battery was made 12 lead acid anchors, weighting almost the same as a cruise ship. Total voltage I measured was around 6.8Volts, so yeah they are a bit toast.



The motor is almost brand new, it's a QS 3000W in 16 inches, so exactly the same I have on my other bike. This motor performs impressively well on my other bike so hopefully this one will too on this one.

I took the bike apart entirely and removed all the crap: All the plastics, the battery, the wiring harness, the handles, brake levers, controller etc won't be reused in this project.



Cleaned everything to get a better wiev of the work to be done.
The steering bearing wasn't turning freely, but it turns out it was still in good shape, only packed with mud and hardened grease. After a short bath in the ultrasonic cleaner I put it back on the bike and it work perfectly.

That was a good opportunity to take some pictures to use later in 3D cad software



The brake calipers looked horrific, my guess is that whoever purged the system left the brake fluid all over and it attacked the paint:



They looked much better after a bit of metal brush:


Started sanding the tank to get a better finish. The plan is to make a mold and do another tank in carbon fiber. The role of the tank will be to protect the controller under it.




I think I will cut the rear frame and build a shorter one. This bike will be a one seater, the main goal will be to keep it as light as possible.
For the battery, I will stick with the A123 liFEPO4 cells since I'm very satisfied with those from my previous builds. Sure they won't be the lightest, but they are durable, they tolerate huge current draw and best of all they are cheap.

I'm not sure yet what controlleer I'm going to use, but it will be at least what I have on my other bike (200A battery/500A phase), hopefully more.
For this build I'll have more time because it won't be my daily driver, so I can do a better work.
I plan to use all the tools I have available at home to build some custom parts, so some parts will be 3D printed, some other will be cast aluminum, tuned on the lathe, carbon fiber, etc. I'll also try to work using 3D CAD from the beginning in order to get a really good looking bike.

 

[j bjork]

Interesting, I am looking forward to the alu casting :thumb:

 

[John in CR]

...For the battery, I will stick with the A123 liFEPO4 cells since I'm very satisfied with those from my previous builds. Sure they won't be the lightest, but they are durable, they tolerate huge current draw and best of all they are cheap...

Awesome bike for free, and already has big room for batteries. Nothing like that available down here. Even used stuff is expensive.

Where do you get your A123's for cheap?

 

[SlowCo]

Will follow your build as your work on the other bike is great :thumb:
Looking forward to what you will make of this one.
And you seem to have a Honda Hawk in the back ground. I have ridden one for years in tuned (65hp) ICE form and loved that bike!

 

[Dui ni shuo de dui]

Thanks for the kind words and the support guys!

Where do you get your A123's for cheap?

I get those on taobao, the local branch of what you would call aliexpress.
I'm not sure if they are new or used ones this time, last time I bought my battery it was used (but really not much, maybe just a few cycles), this time the seller said it is new, so we'll see.
I just bought it yesterday, I asked for two 2P12S batteries that I'll wire in series, so that will be 72V and 40Ah, like my previous build. But this time I chose to split the battery in two so that leaves me more options to fit it into the frame.
Total price was an insane 300USD for both batteries shipped to my door. Unbeatable price, even a battery made of the crappiest cells would be more expensive than that. And I know those celles are really, really good, especially for reliable high power setups.

Meanwhile, I'm preparing the rest of the bike.
I'll try to use the tank to make a mould in order to make two new tanks out of carbon fiber for both bikes. Since I like the clean look of my tank's sportsbike which doesn't have a fuel cap, I've cut the new one and I'm currently making a plug so that it is nice and smooth. I can't use the tank of the sports bike to make the mold for a few reasons, so that's why I have no choice but to work on this one:





Also worked a bit on the frame, removing many useless brackets and cleaning a bit the welds.

I'm a bit more clear about what I'd like to do with this build: Make a very light, weekend focused, summer bike. So that means It will have nothing that is not absolutely necessary: no fenders, no rain protection, minimal lights, no mirrors, turn signals, probably even no key. Nothing but wheels, frame, powertrain and a light carbon skin. The sportsbike will be my choice for all weather riding, this one will be for sunny days!
Well, that's the plan anyways.

Back to the build:
The suspension T steering bracket (I'm not sure what's the correct name for this part in English, sorry) was really looking like crap, the steel casting job was horrific with lots of holes and a very poor surface finish.
I'm not too concerned about its strenght since it's basically the same as my other motorbike which didn't break so far, but this part will be visible since in this case it'll be a roadster. So what I did was to plug all the holes with automotive putty, sand it smooth, put a nice thick coat of grainy primer and then some mate black. Now it looks really nice, much better IRL than on this pic:

And you seem to have a Honda Hawk in the back ground. I have ridden one for years in tuned (65hp) ICE form and loved that bike!

Good eye! Yeas, this one is a japanese imported version, which had the same engine but downsized to 400cc. I really enjoyed it, it was a great bike, the engine sounded awesome, but I stupidly destroyed the oil pump while tightening a screw a few years ago. Took the engine entirely apart to fix it, but then life happened and I never put the engine back together :-(
Maybe one day, but this bike would be illegal to ride and it's difficult to get gas here if you don't have a valid license plate, so it's not on my list of high priorities. A bit sad.

 

[SlowCo]

Good eye! Yeas, this one is a japanese imported version, which had the same engine but downsized to 400cc. I really enjoyed it, it was a great bike, the engine sounded awesome, but I stupidly destroyed the oil pump while tightening a screw a few years ago. Took the engine entirely apart to fix it, but then life happened and I never put the engine back together :-(
Maybe one day, but this bike would be illegal to ride and it's difficult to get gas here if you don't have a valid license plate, so it's not on my list of high priorities. A bit sad.

Just make an electric mid drive (QS138 90H) bike out of the Hawk some day. 8)

 

[Pentti M Reku]

Free project motorcycle? 300$ A123 batteries? Oh dear, that will make some jealous people, including me. Can´t wait to see what will you come up with your mad maker skills!

 

[Dauntless]

Seriously. I remember as a kid it would be tough to come up with $10-20 or such for a project bicycle.

 

[Dui ni shuo de dui]

Ok so I was modeling the bike's frame in my 3D software, and I tried something for fun.

It's a bit weird, but but I quite like it, so now I'm wondering seriously if I should try to build it. Basically the idea would be to go only for the absolute bare minimum: a naked frame, a battery box and that's it. So I'd cut the rear subframe and replace it with one square steel tube and 4 carbon fiber tubes.
Then just some simple carbon fiber panels to hide the battery. I'd have to make the chassis look very smooth and clean and then a nice coat of high quality paint.basically, then it's job done. Super easy, super light, clean look. Not comfortable, that's for sure, but it's not really the point anyways.

I made a few renders and now I'm really tempted to give it a try.






I'll keep working on the battery covers shape a little and I'm still not sure I will do that, but it would be easy to do and also easy to change later if I don't like it so I'm really tempted to go this way.

 

[Dui ni shuo de dui]

Great news, I already received my battery and it is awesome!



The seller didn't lie to me, it does look brand new and unused. He did a really good job cutting it in half, very clean and well done, I'm impressed. The cells were perfectly in balance, each and everyone showed 3.289V. That's promizing.


Here it is, compared with the old lead acid crap: around half the volume and half the weight for a similar voltage and capacity but a much better discharge rate!



Started to cut the rear part of my chassis:



Cleaned the cuts:


Now I'm doing some mockups of the frame I designed, using carboard and some thin tubes I had around:


Also doing a mockup of the saddle. I quite like this shape, but I will do it a bit longer:


There is plenty of space for the batteries and I should be able to fit the controler and the BMS without any trouble:


For the BMS I made a bit of research to see if there was some new interesting products. I hesitated a while between the DALY and the ANT BMS. The Daly seems to have a great build quality, the enclosure is awesome, it is well protected, it has a neat power wire connextion system, features CAN bus and very nice stuff, but two things were a deal breaker for me: apparently you cannot configure it to work with less cells than it's made for (for instance you bought a 32S, it won't work with 24S only, it needs to be exactly the same amount of cells), and also it has a ridiculously low balance current value of only 30mA. It is also twice the price of the ANT BMS at least, even trice for the 500A version I was about to chose.
Those two things were unacceptable for me so I decided to stick with the ANT BMS which comes with no enclosure and some drawbacks like having to solder the gigantic battery cables, but who is more flexible and allows for still low but at least not ridiculous balancing currents (200mA).
I've ordered the 32S 300A version, this way I can add a few battery cells later if I ever want to.

So far it is going nicely, next will be to actually make the frame out of steel instead of carboard

 

[Dui ni shuo de dui]

Cut some tubes and tack welded together:


Also made some changes on my design, the saddle is now quite larger and features a bottom cover that will be made of carbon fiber. I plan to make the seat part out of silicone and cover it with some nice leather, I don't know if silicone works fine for a seat, guess we'll see.





3D printed a first version of the saddle to see how it fits. I think it's nice but a tad too narrow and it needs to go towards the front of the frame a bit more. So I'll just print another one later.


I've also 3D printed some fittings for the side tubes. Those are only to check if the design is ok, the plan is to cast the final ones out of aluminum. The tubes themselves will be made of carbon fiber.





I can't be sure until I make the foot pegs, but so far it seems like it won't be too uncomfortable. I tried to sit on the bike and it was ok, even if the seat is made of hard plastic for now. I think the final version should be all right if I can find a good placement for the foot pegs.

I ordered some nice candy pearl red to paint the frame as well as the brake calipers. Also ordered a really nice paint gun, I hope this time I'll be able to do a great paint job on the frame, I'd really like for it to look professional. That means a lot of preparation to make the frame spotless before painting it.

The BMS arrived so maybe I'll start working on wiring it in the next few days.

 

[Dui ni shuo de dui]

Mhhh, this thread is a bit quiet, feels like I'm just talking to myself here :lol:
Anyway, I'll keep talking, in case anyone follows.

So there was a bit of progress during the past two weeks:

I 3D printed the most gigantic part I ever printed on my new 3D printer:


This is a fist mockup of the battery covers, the goal was just to see if the dimensions I took while modeling the chassis in my 3D software were accurate. Turns out they were pretty much spot on, there's very little adjustment needed in my drawings.



The final part will be made of carbon fiber, but I'm not decided yet as to how exactly. I hesitate between 3D printing the final version out of plastic, then fiber carbon wrap it, of 3D print a mold and do the part with 100% carbon fiber. I'd like to give the second solution a try since it's something I've never done yet, but it will be a really huge print and lots of work to prepare the mold.

Next, I received my carbon fiber tubes, so I cut them to lenght and 3D printed some fittings. For the final version, my plan will be to make these fittings by casting some aluminum then bond these to the tubes using epoxy. Not sure exactly yet if I'll use sand casting or plaster, and I hope that I will be able to get a decent enough surface finish. If not, then I'll consider using CNC instead.
Anyway, the tubes look nice:








Finally, I fully welded the frame. It turns out that whoever welded the frame at the factory did a horrific job, some welds were cracked, there were many holes in some really important structural spots... Good thing I took the time to mod the frame, otherwise I wouldn't have seen these.




Just horrific.
Anyway, I tig welded all the frame. I'm far from being a pro, this is actually only the 3rd time I weld anything on my projects, but I think I did better than whoever welded it in the first place:








Now the frame is almost done, I just have to weld a few brackets for the carbon tubes, the foot pegs as well as the stand. The stand will be made out of a carbon fiber tube and aluminum fittings, similar to the rear frame tubes. For the foot pegs, I haven't really put a lot of thought in these just yet, probably some carbon fiber tubes also but with a bigger diameter, or maybe also some aluminum casting, we'll see.

 

[Chambers]

Looking good! Subscribed

 

[Chambers]

How big is that 3d printer? Custom built?

 

[Dui ni shuo de dui]

Yeah, I just finished build it a few weeks ago, it's entirely my own design. If you're interested to see the build thread you can check there:
https://forum.v1engineering.com/t/mpcnc-made-in-china-new-build/19393

The print volume is 720 x 720 x 600 mm, and the outside dimensions of the machine are 1000x1000x1400mm, it's really big.

 

[Chambers]

Yeah, I just finished build it a few weeks ago, it's entirely my own design. If you're interested to see the build thread you can check there:
https://forum.v1engineering.com/t/mpcnc-made-in-china-new-build/19393

The print volume is 720 x 720 x 600 mm, and the outside dimensions of the machine are 1000x1000x1400mm, it's really big.

that's awesome! Thanks for the link

 

[SlowCo]

Mhhh, this thread is a bit quiet, feels like I'm just talking to myself here :lol:
Anyway, I'll keep talking, in case anyone follows.

Great work again and a serious pace in making progress :thumb:
No need to worry as more and more people will discover this thread and follow your build.

 

[Dui ni shuo de dui]

Thanks guys :wink:

A bit of progress yesterday, I cut and welded a few little tabs in order to set definitely in place the carbon tubes:




Now the frame mods are almost completed, I just have to make a bracket for the stand and possibly a few brackets inside to frame to better hold the batteries. Also have to machine some round bars and weld them to the frame in order to attach the other side of the carbon tubes.

I'll start working on the rear light this weekend, I found some LED strips and thought of some interesting design. I printed a mockup in red just to see if it would be visible enough and I think it'll be just fine:



I'm also working on fitting the batteries in the frame, so far it seems all right with this 3D printed system. I'll see later how I'll build something more durable, Probably some steel brackets and carbon fiber:





I bought a professional paint gun and trying to learn how to use it. I'm experimenting with the rear caliper: removed the old paint, cleaned it well, gave it a good coat of primer andthen a good coat of red paint. Looks really great IRL, but my phone is pretty bad at capturing red colors for some reason, it should look more like a Ferrari red. Later on I will try to add the layer of candy pearl red on it, I hope it'll look good!

 

[Shazzy]

Build is looking really nice!

 

[Dui ni shuo de dui]

Thanks Shazzy!

I had some more 22mm carbon tubes, and since I'm confident this stuff is very solid now and since the handlebars were the same diameter, I decided to make handlebars out of it.
It was easy to make, Just had to cut two bars of the same lenght, then gave both a bit of lathe work to get a perfectly square end, and finally made those little endcaps out of aluminum:



I really didn't like the look of the orange anodized parts. They do look ok sometimes on pictures, but in real life they look really cheap and it won't be a good fit for the color scheme I planned for the bike anyway.
So I did a bt of chemistry to remove the anodization.

A long time ago, I bought some chemicals to do DIY anodizing at home. Turns out that I never actually did it, some other projects came and I didn't need to do it anymore. Anyway, I had a stock of some chemicals, in particular sodium hydroxyde (caustic soda or NaOH).
After a bit of Google search, I found out that this works really well to remove the anodizing on aluminum parts, so I decided to give it a try.

I poured water in a bucket then put a random amount of sodium hydroxyde flakes in it. First I tried with some random part I had in the shop. After 5 minutes it turned like this:


I was now confident it would work, so I placed the main part of the steering assembly in the bucket:



After a few minutes it started bubling and I could see the orange color slowly melting away.
I left it around 10 minutes then took it out of the bath, and it looked like this:



The picture makes it look like it's a plain color, but it was a really interesting and weird petrol like or maybe flamed titanium appearance, with red, yellow and deep purple shades. It looked really, really cool in real life, even though it doesn't look good at all on the picture. Unfortuntely this wasn't a durable finish, I could just scratch it with my fingernails, so I decided to use the brush weel to buff up the part to a more common appearance.

Gave it a perfectly fine finish. The damage near the steering column hole was already there before so that's not due to the soda bath.


Then I gave the same treatment to the handlebars clamps, as well as the fork tubes caps:




I'll need to do the same thing for the fork tubes, but my bucket is obviously too small. I have to find some kind of PVC tube large enough to fit one fork, then it should be easy.
I'm not entirely decided yet on which color will be used for which part. The tubes will likely end up black, but I think I'll decide this in the very end after I paint the frame.

 

[j bjork]

I like where you are going with the design :thumb:
Something different, that dosent look like a converted gasbike.

It will be interesting to see how this anodizing turns out. I have seen the kits too, but never got around to try.

I wonder about the inside of the fork tubes, they will probably be treated with something too.
Hopefully something more wear resistant. Do you plan to seal them somehow when you do the treatment?

 

[Dui ni shuo de dui]

I wonder about the inside of the fork tubes, they will probably be treated with something too.
Hopefully something more wear resistant. Do you plan to seal them somehow when you do the treatment?

Ooohhh that's a really great remark, thanks a lot for bringing it out!
I haven't thought about that at all, indeed using the sodium hydroxyde inside the tube might very well ruin it!

I'll have to find some way to avoid it entering the tubes. Not sure yet how I'll do it, so any idea is welcome.
Thank you very much for this question, it probably saved me from doing an expensive mistake!

 

[SlowCo]

What a very nice look and finish of those aluminium parts. Great result! As for the fork tubes you could probably seal them of with temporary plugs glued in/on top and bottom using silicone sealant/glue. Making them "watertight" when submerging them in PVC tubes. I hope you'll get the same finish on the fork tubes as the other aluminium parts and not turn them black 8)

 

[MorbidlyObeseKoala]

Really taking shape, jealous off your workshop too.

My first thought on the NaOH on the fork was make it a thick slurry and paint it on with a brush and wipe off after 5-10 minutes. Ideally less mess and more control over where it touches. I'd get some elbow length gloves before doing it though, acidic burns you can feel quickly but basic chemical burns take off a lot of skin before you feel them according to some old chemistry professors of mine.

 

[Dui ni shuo de dui]

Really taking shape, jealous off your workshop too.

My first thought on the NaOH on the fork was make it a thick slurry and paint it on with a brush and wipe off after 5-10 minutes. Ideally less mess and more control over where it touches. I'd get some elbow length gloves before doing it though, acidic burns you can feel quickly but basic chemical burns take off a lot of skin before you feel them according to some old chemistry professors of mine.

Thanks mate, much appreciated!
My workshop is really small though, I wish I had more space...
For the tubes, I'd really prefer to dip them entirely instead of brusing them because I suspect brushing will take forever and also I fear that the finish will be inconsistent.

What a very nice look and finish of those aluminium parts. Great result! As for the fork tubes you could probably seal them of with temporary plugs glued in/on top and bottom using silicone sealant/glue. Making them "watertight" when submerging them in PVC tubes. I hope you'll get the same finish on the fork tubes as the other aluminium parts and not turn them black 8)

Thanks SlowCo!
Yeah that sounds like a good plan, the silicone is a good idea I think I'll do just that!