1989 Kawasaki EX500 (Ninja) - EV conversion, finished but still refining

[harrisonpatm]

All good ideas, but mostly it's bad light because it's my cellar-access, dirt-floor basement, whose only light is a bunch of random LEDs I've already put up from different pieces of scrap over time. I've reached a point in my workspace of diminishing returns regarding how much upgrading I'm able to put into such a small, crappy space. If I ever move house, it needs to have a garage.

 

[amberwolf]

Any yard space for a shop-sized storage shed?

I use one of my sheds as a workspace when I have to work on things in wet weather, for instance, but usually I work on most of the trike / etc stuff in the yard itself, often under a tree for shade.


I suggested the bar lights because they're relatively cheap, really easy to put up, and can be used anywhere, and just plug right into an outlet so no wiring work needed.

(These days, if things are hard to do or take a lot of work, I'm very unlikely to ever do them or use them, no matter what my intentions and desired might be ).

 

[harrisonpatm]

Any yard space for a shop-sized storage shed?

Nope! Postage-stamp sized plot with a small house where my wife has all gardening privileges. I don't mind the basement, the low light really is only apparent when I try to take a picture of something. And I don't worry about getting things dirty, when it's already concrete walls and a bare dirt floor. In the summer I bring pieces upstairs and outside to work on, and on the finished motorcycle(s?), I've built a roofed open-sided parking space where I can spread out and work as well.

 

[harrisonpatm]

Revisited the 3d-printed brake lever. I know at this point it'd be easier to just buy one, and it's slowly approaching being cheaper to just buy one, but way less fun! I finally acquired and modded up my printer to be able to print carbon-fiber infused nylon, which is basically one of the strongest things I can print without getting a whole different printer. Something I've been looking forward to using for awhile. And holy crap, it's so strong!


When researching tips and tricks for using this filament, I kept getting directed to various forums for 3d-printing firearms and associated parts for firearms. So if it's good enough for that... One of the tricks was to "anneal" it post-printing, a chemical process that I don't understand=, but is supposed to make it even stronger and prevent layers separating. If this is to be a brake lever under regular stress, I'll want it to resist weathering. Anyway, you're supposed to heat it to 80 degrees C and keep it there for 6 hours. I have a homemade sous vide machine from my days as a chef, so let's give that a try. It's super weird, basically boiling plastic to make it stronger and it hurts my brain to think about it, but other people online say it works great.

Top is un-annealed, bottom is annealed.

Can't see a visual difference, and I'm not about to waste my expensive filament by putting it through stress tests, but the results seem good. At the very least, I was surprised to see that 6 hours in hot water didn't warp it at all. Crazy.

 

[harrisonpatm]

Alright, thanks @A-DamW , great drawing program recommendation. Throwing my 12V wiring harness up for comments and critique:

Finally got off my butt and made up a 12v wiring harness. I always give myself more of a challenge than I need to, because I make a point of not purchasing new rolls of wire and just using what I've collected from scrap and recycling projects. Normally I don't mind, but when it comes to a wiring harness, it makes it hard, always looking for relatively long lengths, usually of a specific color. But I do try to just use a gauge something like double what I actually need, since all the wire is free and it's not like I'm adding cost or weight by using 16awg when 20awg would do just fine. Less resistance that way, and I don't have to worry about wires heating up at all.


Not going to wrap it up yet, because who knows if I'll need to add anything on the final build, but it's rather nice to know that I have a big section of the bike done, and it's basically just waiting on a powertrain.

On an interesting note, I used an ammeter to get an idea of the total 12v current draw. The front headlight is newly purchased LED, and the rear tail light/ brake light is the original fixture, but new LED bulbs. I kept the original rear turn signals, incandescent bulbs and all, and it was crazy to see the rear blinkers needing 2 amps, while the rest of the system draws only 2-3 amps, with the headlights on full blast. I guess LED's really do save a lot of energy after all! No reason to switch out the rear blinkers, I'm not actually worried about the power draw. Maybe if I see a good deal later on or something.

 

[harrisonpatm]

I think I just scored big. I make some casual scrapyard runs, not as a profit-making venture, just to bring my accumulated scrap metal somewhere good, as well as to get dirt cheap prices for copper wire. Well, I happened upon these on my trip today:




3-phase BLDC, looks like its got hall and temp sensors, and judging by its weight and wire gauge, looks in the range of 3000-4000w. Also looks like it was used for some sort of high-powered pump, based on what was left on the shaft. And I got it for $6USD! So of course I got 3. Time for some investigation to see if they can be mounted as a mid drive. At this price I wouldn't feel bad about running one over its rating, burning it out, and just swapping it for another one!

Anybody have any info on these? Closest I could find so far is this. The model numbers don't match up though, its possible what I have is something out of production.

130BSA Series-3X MOTION TECHNOLOGIES

PERFORMANCE DATAOUTLINE MAP

www.3xmotion.com

 

[Eastwood]

Good price on the motor but not good for moto conversion.

First off those phase wires are to small, looks like they’re good for maybe 50 continuous amps

The specs say peak current of 12 amps
The rated power is 1,570watts. To small

Then is has max torque of 5.5nm which is nothing.
As a reference the qs138 v3 70h has 98nm torque and that’s about the smallest motor you would want to put on a motorcycle.

I’m sure you can find use for those motors, but definitely not a motorcycle conversion. It would hardly have any acceleration. The only way around this is to rewind the motor. Whatever this motor was used for it obviously did not require any torque. Like you mentioned, the part numbers don’t match up exactly but it’s just one number different so I’m sure it’s similar to those specs listed.

 

[amberwolf]

Closest I could find so far is this. The model numbers don't match up though, its possible what I have is something out of production.

Or a custom version for a specific OEM.

Most pump motors are not high power, but are continuous duty at the power they do make.

Assuming the specs on that one are similar to those on that page, then if you use it with a gearbox or other reduction drive, you can convert the ~3000RPM down to say, 300-500RPM at a wheel, and get 6-10 times the torque, but that's still fairly low, 25-50Nm.

 

[harrisonpatm]

I knew it could have been a long shot, but I couldn't pass it up for the price. I was considering replacing phase wires anyway. And the online specs for what looks like a similar motor do say it's supposed to weight 5 or 7 kilos, while the ones I got are 10-12 kilos, depending on whether you count the cables. So fingers crossed, I send an email to the company directly, maybe I did get lucky.

I can always use one for my wind turbine experiments. And as @Eastwood pointed out, I can use them for a different smaller conversion, probably. Like a little scooter.

 

[Eastwood]

I can always use one for my wind turbine experiments.

Since you have a few of them, you could try rewinding for more torque. It would be a good learning experience and plus make the motor usable for a scooter. The motor as is, would be low torque for a scooter, but with the proper copper windings, you could achieve higher torque.

 

[amberwolf]

Rewinding for more torque reduces the speed (raising kT reduces kV). You can do the same thing, effectively, by simply using a reduction in the drivetrain between the motor and the wheel.

Still the same amount of power either way, unless you can fit enough more copper in the windings to allow enough more torque to more than compensate for the speed reduction.

 

[harrisonpatm]

I heard back from the manufacturer directly, and @amberwolf was right:

Or a custom version for a specific OEM.

It was a custom production and I was given the electrical specs. It's rated for 2200w. So I was right too, the motor was heavier and more powerful than what I could find on their website. Unfortunately, @Eastwood was right as well, it's not enough for a motorcycle. Would be perfect for a small scooter or moped conversion though, if you keep it under 35mph.

I'm in southeast Michigan, if anybody is in the area and would like one to play with.

 

[SlowCo]

That looks like an ideal motor to overvolt/power to 60V or 72V and 100 amps peak. Just keep an eye (better: a sensor) on temps.

 

[harrisonpatm]

That looks like an ideal motor to overvolt/power to 60V or 72V and 100 amps peak. Just keep an eye (better: a sensor) on temps.

Indeed, I already am mentally putting together a potential build, if I see a small donor moped on my local classifieds. The motor already has a temp sensor in place, so it's just begging to be built at this point. Yay, another project!

 

[Eastwood]

Rewinding for more torque reduces the speed (raising kT reduces kV). You can do the same thing, effectively, by simply using a reduction in the drivetrain between the motor and the wheel.

Still the same amount of power either way, unless you can fit enough more copper in the windings to allow enough more torque to more than compensate for the speed reduction.

Right, but he’s mentioned he’s limited on fabrication so a jack shaft would not be an option for him. That’s why I was suggesting to rewind the motor for torque.

 

[amberwolf]

Right, but he’s mentioned he’s limited on fabrication so a jack shaft would not be an option for him. That’s why I was suggesting to rewind the motor for torque.

Sure; I was just pointing out that it would be easier to put the reduction in the drivetrain itself than rewinding it.

Some probably useless thoughts, since they were in my head anyway:

It shouldn't need a jackshaft, depending on the space available for sprockets and what drive method is used. The motor wouldn't be directly driving a wheel, since it would be sticking pretty far out the side of any two-wheeler that way so it would need to drive a gear or belt sprocket (or a gearbox that would then drive a chain or belt sprocket), so the reduction could be done right there by using a small motor sprocket and large wheel sprocket, just as you would with any other higher RPM motor. Depending on the wheel size and speed desired, it might need 10:1 to 13:1 or so reduction, which is possible in a single reduction with the right sprocket type, even if it looks odd. Say, a 10 or 11T on the motor, and 100-130T on the wheel.

Not very power-tolerant but 25H chain sprockets are definitely available for 90+ tooth counts (I think I actually have one around here somewhere in that range that I'll probably never use). Larger / more durable chain sizes would need larger diameter sprockets, and that might get awkward with smaller wheels or lower speeds (that need even larger reductions).


BTW, fabrication doesn't always have to be done completely custom--i've learned over the decades to misuse repurpose bits of other things whole to do things I needed done that they weren't used for originally. Just takes some pondering to figure out what things would have the stuff I need in them, then acquire one and rip it's guts out scavenge the bits I need, and often just clamp or bolt all the bits together (not having a welder until the last decade or so I found many ways to do those things instead). Most of these methods are durable enough if done right. When they aren't then they just get redone until they are.

 

[harrisonpatm]

Sure; I was just pointing out that it would be easier to put the reduction in the drivetrain itself than rewinding it.

Some probably useless thoughts, since they were in my head anyway:

It shouldn't need a jackshaft, depending on the space available for sprockets and what drive method is used. The motor wouldn't be directly driving a wheel, since it would be sticking pretty far out the side of any two-wheeler that way so it would need to drive a gear or belt sprocket (or a gearbox that would then drive a chain or belt sprocket), so the reduction could be done right there by using a small motor sprocket and large wheel sprocket, just as you would with any other higher RPM motor. Depending on the wheel size and speed desired, it might need 10:1 to 13:1 or so reduction, which is possible in a single reduction with the right sprocket type, even if it looks odd. Say, a 10 or 11T on the motor, and 100-130T on the wheel.

Not very power-tolerant but 25H chain sprockets are definitely available for 90+ tooth counts (I think I actually have one around here somewhere in that range that I'll probably never use). Larger / more durable chain sizes would need larger diameter sprockets, and that might get awkward with smaller wheels or lower speeds (that need even larger reductions).


BTW, fabrication doesn't always have to be done completely custom--i've learned over the decades to misuse repurpose bits of other things whole to do things I needed done that they weren't used for originally. Just takes some pondering to figure out what things would have the stuff I need in them, then acquire one and rip it's guts out scavenge the bits I need, and often just clamp or bolt all the bits together (not having a welder until the last decade or so I found many ways to do those things instead). Most of these methods are durable enough if done right. When they aren't then they just get redone until they are.

This is all in my head as a possibility if the project ever does move forward as a mid-drive. At some point I'll need to give myself a primer on selecting the right chain and gear sizes.

TW, fabrication doesn't always have to be done completely custom--i've learned over the decades to misuse repurpose bits of other things whole to do things I needed done that they weren't used for originally. Just takes some pondering to figure out what things would have the stuff I need in them, then acquire one and rip it's guts out scavenge the bits I need, and often just clamp or bolt all the bits together (not having a welder until the last decade or so I found many ways to do those things instead). Most of these methods are durable enough if done right. When they aren't then they just get redone until they are.

You and I are on the same page there. I do like to save nice looking gears or transmissions from stuff I salvage, just in case

 

[harrisonpatm]

Starting to gather a list of parts to finish the build this year, now that I'm basically finished with my moped conversion. I'm gonna focus on the battery the next few months (I came up with what I think is a decent plan for it). While I'm thinking about it, has anybody used higher-voltage DC/DC converters, up to the 120v range? I want to keep my current charging situation, i.e., I use a boost converter from my home 14s powerwall, and boost to 83.6v for my 24s LFP battery. This has worked great for me for almost two years, and it's a very efficient use of my solar system, in that I don't have to do a DC-AC-DC conversion. If I move to 28s, however, it's harder to find off-the-shelf components in that voltage range.

What I've found so far is this:

https://www.amazon.com/gp/product/B01GFVI6R6/ref=ox_sc_act_title_1?smid=ATVPDKIKX0DER&psc=1

And it's no so expensive, but my total charge voltage will be 116.2v (4.15v x 28s), so I don't like the idea of pushing it's voltage limit. Plus my theorized battery is looking like 9kwh, and this thing is only rated for 900w. It's also never a good idea to run it at its limit, so I'd likely only use like 500-600w of charging, meaning it'd take like 20 hours to fully charge the battery. I don't mind slow charging, its better for battery life anyway, but 20 hours might be a little too slow.

(currently I use this, the 1800w model, which can boost to 90v apparently. Since I only take it to 83.6, and only max out at 1200w charging, this is likely why it's lasted so long)

Perhaps the solution is to buy 2 of the above product and run them in (fused) parallel? Not only would that still give me the option to just use 1 of them if I can afford a really slow charge, but also I would have a backup is one of them fails. Starting to like this idea...

But also, if anybody has any product recommendations for a reliable boost converter that would take nominal 48vdc input and boost to 120v+, I would appreciate any advice!

 

[harrisonpatm]

Another piece of advice I'd like from the internet:


My current plan to fix a battery in there. This is a 8mm sheet of aluminum. I want to bolt it to the frame, from underneath as shown in the picture, because the top sections of those tubes are too uneven for a flat plate, and I want the extra 40mm of vertical space for the battery I'm planning. The battery will essentially sit fully on this sheet. There will be some cradling at the top half, but that will just be for position keeping, not going to take much weight. I'm not worried about the sheet itself taking the weight of the 50kg of planned battery, and even if I was, I could always get a thicker gauge or use steel instead.

What I'm asking the crowd is, do you folks think that fastening this from underneath with 4-5 thick bolts will be strong enough? I trust 4 bolts for static tension, but my worst-case scenario is hitting a pothole, and the sudden downward momentum of the 50kg battery is enough to shear the bolts straight off. How likely will that be in this setup?

I can also possibly use two of the original motor mounts to secure the battery case itself, but for now I want to plan/assume that all the battery's weight will be on 4-6 bolts. Thoughts?

 

[Eastwood]

What I'm asking the crowd is, do you folks think that fastening this from underneath with 4-5 thick bolts will be strong enough? I trust 4 bolts for static tension, but my worst-case scenario is hitting a pothole, and the sudden downward momentum of the 50kg battery is enough to shear the bolts straight off. How likely will that be in this setup?

I can also possibly use two of the original motor mounts to secure the battery case itself, but for now I want to plan/assume that all the battery's weight will be on 4-6 bolts. Thoughts?

Where would the 4-6 bolts be located exactly? You mention “fastening this from underneath”.. but what’s the plan for the placement for the bolts?

 

[harrisonpatm]

Where would the 4-6 bolts be located exactly? You mention “fastening this from underneath”.. but what’s the plan for the placement for the bolts?

Drilling holes through both the frame and the plate, 2-3 on each side. Bolts would be vertical. Does that make sense?

In the above picture, there's two sharpie marks on either side of my thumb, that's what I was thinking

 

[Eastwood]

Drilling holes through both the frame and the plate, 2-3 on each side. Bolts would be vertical. Does that make sense?

In the above picture, there's two sharpie marks on either side of my thumb, that's what I was thinking

I don’t know how I feel about drilling holes in the frame, I would avoid it. You could make some brackets that hold the plate into place.

So is your frame steel? And then the plate is aluminum… obviously welding that bottom plate to the frame would be best, but not really possible with two different metals.

Edit:
OR….
If you could get someone to weld you some sturdy tabs coming off the bottom plate at 90° you could use those existing bolts. Not sure if you have the same bolts on the other side?

 

[harrisonpatm]

I unfortunately do not have the same bolt holes in the other side, those are just the mounting holes for the side stand.

In general I agree with your advice to not drill holes in a frame haphazardly. My thought was that the frame modification I'm planning is limited enough to not affect the structure too much. If I were to drill through holes horizontally, the downward stress of the battery's weight would be perpendicular to the new holes in the frame, and that would be bad. By making vertical holes like I'm currently planning, the steel on the lateral sides of the frame bars would be unmodified, and the downward battery weight would be parallel to the new holes, thus the strength of the frame in that respect should be unchanged.

I'm certainly no expert in this though, and in any case I was planning to sit on this for a few days to mull it over. Your bracket idea is good, I'd be worried about the brackets themselves failing, but I'll have to consider that.

I also did research on bolts and it seems like if I got Grade 8 bolts, their pull-out strength is strong enough for this purpose

 

[TorgueRPM]

By making vertical holes like I'm currently planning, the steel on the lateral sides of the frame bars would be unmodified, and the downward battery weight would be parallel to the new holes, thus the strength of the frame in that respect should be unchanged.

With force being applied to the top of the tube, the top/bottom of the tube would be in compression/tension, so I'd think any material removed would weaken it. Maybe not as much as a horizontal hole though.
Also, even in the older cradle frames, I think the engine did play some role in frame stiffening, so using the battery box in the same way would probably be a good idea.

 

[harrisonpatm]

With force being applied to the top of the tube, the top/bottom of the tube would be in compression/tension, so I'd think any material removed would weaken it. Maybe not as much as a horizontal hole though

Thank you. Taking all this intro consideration