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

[jkrienert]

That is a cool electric eel aquarium. Kudos on the design and fit. Gives me a strong urge to get into the 3dprint movement.

 

[harrisonpatm]

That is a cool electric eel aquarium.

I actually did laugh out loud reading that, so, LOL.

Kudos on the design and fit. Gives me a strong urge to get into the 3dprint movement.

It's a great resource for amateur builders of any hobby. People like me who don't have a CAD or fabrication professional background, it's just so great. I certainly overuse it; probably about 10% of the motorcycle got 3d printed.

 

[harrisonpatm]

Got the QS273 installed on the swingarm today, just before it started raining.

One of the biggest weaknesses of my previous build was the hub motor mount. Technically it worked: I used the stock (loose) torque arm plates, overtightened the nuts on the axle, and drilled for a cotter pin. So it never loosened or wiggled, and it never fell off. But I have since learned how lucky I was, and it was also a pain to precisely mount just the right way to line up the cotter pin again, when I wanted to take it apart for maintenance.

Pics below are from the previous build's mount:


Ugh, really ugly looking at it now.

Anyway. I spent a ton of time designing around that issue for this build. So I shouldn't have been surprised at how easily it went together, and how frickin secure it was when I was finished. And yet, here I am pleasantly surprised.





It took more time to align the brake calipers and find the correct arrangement of washers/spacers than it took to actually mount the motor.

Really want to put it on the bike now, but it's about to rain, I'll have to wait till tomorrow. So close!

 

[harrisonpatm]

It's alive!


Lots of little cosmetic things to play with to make it a bit tidier. I also need to play with the controller settings and see what it's capable of. Plus range tests, need to build my charger, ect...

But I did take it out for a couple short jaunts. Got to 70mph on my regular, non-boost mode, peaking at only about 100 amps (@ 95ish volts, so call it 9.5kw). That was with no controller tweaking, and batteries only discharging at 1C. Really looking forward to playing with this!

 

[Buildsix]

How is the acceleration form the hub motor? Also do you know what your final bike weight is?

 

[harrisonpatm]

How is the acceleration form the hub motor? Also do you know what your final bike weight is?

Acceleration is great, feels the same as it used to, just gets up to a higher top speed. I can and will tune the settings for better acceleration, but personally, I'm not a thrill seeker. The bike is my commuter, errand runner, daily driver, occasional joy rider, energy efficient off-grid transportation. I don't race or burnout.

Next week I'll take it to my scrapyard and get it weighed.

 

[Buildsix]

Acceleration is great, feels the same as it used to, just gets up to a higher top speed. I can and will tune the settings for better acceleration, but personally, I'm not a thrill seeker. The bike is my commuter, errand runner, daily driver, occasional joy rider, energy efficient off-grid transportation. I don't race or burnout.

Next week I'll take it to my scrapyard and get it weighed.

The reason I ask is that I've also got a street triple as well so have gotten used to sub 4 second acceleration. One of the reasons I stopped riding my donor bike is that it was just so damn slow and the brakes were terrible. The power model I made shows roughly 6 second for a 0-100kph (0-62mph) with the 8kw hub motor using rubbery torque figures from QSMotor, but every spec they release seems to have different numbers so I'm not confident in what it actually will be. Plus I realise some of this will also be down to the motor controller and battery outputs but I am curious as to how these motors go on 100V in general.
If it can hit 6 sec 0-100 accel rate then it will be easily usable I feel.

 

[harrisonpatm]

f it can hit 6 sec 0-100 accel rate then it will be easily usable I feel

It can. I could get back to you later when I start testing it out, but yesterday it felt like my 0-100kph was less than 6 seconds for sure. On regular non-boost mode, no tuning, with a 95volt battery. So yeah, I'd go for it. Like you said, it'll be dependent on which controller you're using, and how well you batteries can handle higher amp draw.

Higher voltage battery is the main reason I wanted to do this build, and it seems like it'll pay off.

 

[jkrienert]

Been facing some serious struggles with my build, and seeing your success is a great catalyst. Kudos on things coming together. Looks awesome, and sounds like it purrs that way too.

 

[harrisonpatm]

Been facing some serious struggles with my build, and seeing your success is a great catalyst. Kudos on things coming together. Looks awesome, and sounds like it purrs that way too.

Thank you! Good luck on your build. I just worked on mine for a few hours a month, for over a year. I only got busy doing stuff in the past two weeks or so, trying to put all the components together. It happens eventually.

 

[Buildsix]

It can. I could get back to you later when I start testing it out, but yesterday it felt like my 0-100kph was less than 6 seconds for sure. On regular non-boost mode, no tuning, with a 95volt battery. So yeah, I'd go for it. Like you said, it'll be dependent on which controller you're using, and how well you batteries can handle higher amp draw.

Higher voltage battery is the main reason I wanted to do this build, and it seems like it'll pay off.

Thats great to hear. I’ve used a Kelly 8080I which is rated to 500A. My pack uses 74Ah pouch cells which are rated at 2C continuous and 3C burst so it should be fairly well matched to the motor.

How are you finding the wheel balance? On the one I have the casting is a bit off and has a bit of vibration on the bench.

 

[harrisonpatm]

How are you finding the wheel balance? On the one I have the casting is a bit off and has a bit of vibration on the bench.

It's not easy to balance with all that weight, that's for sure! Ive gotten it better than it was, but it does still vibrate a bit.

I used this method. FYI, this guy is a little bit hilarious

 

[Buildsix]

Awesome, that actually looks fairly painless. But I’ll be sure not to have that much coffee

 

[harrisonpatm]

Almost made a big mistake! Remember that lovely cover for the BMS on top of the battery lid?


Well it turns out, it completely restricts air flow! Gee, who would've thought?

I was slowly charging and I had turned on the BMS's balance function, for a top balance. Good thing I was monitoring. The mosfet temps went from 25 C to 60 C in an hour.

Easy enough to fix, but felt really dumb for a minute.


Tempt went back down to a much more reasonable 45 C.

 

[harrisonpatm]

Accessories! To make sure that I can always diagnose and fix issues on the road if I need to. Tool roll brackets, velcro attached:


A slot on the side for 3ea 18650s, for my emergency 12v supply:


And a slot on one side for a cheap multimeter


I totally get that it might look messy to most, with all the stuff just kinda clamped on, but I personally like it, because the whole bike looks like that and I prefer function over form.

 

[jkrienert]

Wonderful precautions with the onboard service equipment. Especially the emergency 12v supply. I'm definitely going to include something like that. It will probably be the only NMC size I'm currently confident enough to include on the LTO system I'm working on.

I just had a post in another forum that leaves some concern for my own build, which I hope to post someday... Anyway, I'm using some prefab PVC 5" square to house prismatic modules. The caution shared with me was PVC is hazardous and caustic when ignited, and the better design choice is ABS or PC. Now, if it gets to the point of ignition, I've got other problems... and on a 2 wheel EV inhalation hazard is lesser, which since it was on a electric car forum, that was likely their stance. Yet, im presently wrestling with with how to mitigate my design...

And I realize by your post that... Most 3D prints like yours are ABS or some non PVC plastic, and (one of the) safe(est) materials for the type of construction were vested in?

 

[harrisonpatm]

Wonderful precautions with the onboard service equipment. Especially the emergency 12v supply. I'm definitely going to include something like that. It will probably be the only NMC size I'm currently confident enough to include on the LTO system I'm working on.

I just had a post in another forum that leaves some concern for my own build, which I hope to post someday... Anyway, I'm using some prefab PVC 5" square to house prismatic modules. The caution shared with me was PVC is hazardous and caustic when ignited, and the better design choice is ABS or PC. Now, if it gets to the point of ignition, I've got other problems... and on a 2 wheel EV inhalation hazard is lesser, which since it was on a electric car forum, that was likely their stance. Yet, im presently wrestling with with how to mitigate my design...

And I realize by your post that... Most 3D prints like yours are ABS or some non PVC plastic, and (one of the) safe(est) materials for the type of construction were vested in?

If you're talking about just the housing and mounting for you batteries, that's it's own issue. I used 3d prints to "help" mount the battery, but the work is really mostly being done by aluminum plate, steel bars, ratchet straps and polycarbonate sheets. And as you point out, if you're having such a bad day that your batteries are on fire, the material in which is housed is going to be the least of your worries.

For everything else on the bike that's 3d printed, I've used a variety of filaments, depending on use case and what I need them to do. I actually don't use ABS, because the S is styrene and I have young children in my house who don't need that in their lungs or brains. I know an argument can be made that 3d printing any material ejects microplastics via extruding out of a hot nozzle, and all I can say is that I make the best choices that I can with the information I have, and that I have to pick and choose my battles.

I'm mostly using PETG for my prints on the bike, it has good strength, not too brittle, good UV resistance, good price. In some things I've also used PETG reinforced with carbon fiber or fiberglass, if I want the extra stiffness. I have TPU for the handlebar grips, some spacers or washers, switch mounts on the handlebars. The battery's lid, underneath the tank that's holding down the battery, is actually PLA. That sounds like a bad idea, but PLA is one of the stiffest and strongest materials that you can print. Its weaknesses are that it crumbles when exposed to UV (which this won't because it's under the solid metal tank) and it cracks/shatters when overstressed, rather than bend. I've printed that piece with lots of material, 5-20mm thick is most places. It's also not the only thing holding down the battery, I have ratchet straps and a screwed lid (lots of redundancy).

In a couple small places, like the front and rear battery brackets, I've used glass-fiber reinforced nylon, which is one of the strongest materials that my printer can handle without immediately stinking up the house or poisoning the kids. But it can be a bit expensive, and harder to print, so I've only used it a couple of times. Also, I've recently come across PCTG, which has been staggeringly good for me. It's stronger than PETG without being stiffer, prints hotter, better layer adhesion, better finish, not too expensive, and not too difficult to print. As far as I can research online, PCTG is one of the most chemically stable filaments you can get (its non-3d-printed uses include food containers, water bottles, ect). It's my current favorite filament.

 

[jkrienert]

So much knowledge shared, in a earthly first hand way, thanks for this.

I had no idea glass reinforced polymer could be 3d printed. I know of it's qualities at minimum by how long my power tools casing have survived. The PCTG is also intriguing. All these insights leave me wondering why I haven't brough a 3d printer into the shop yet...

Your reference about young ones being a design factor, is similar to my situation, and a good example of when we build things, there is often much more than meets the eye in the result. It's comforting hearing that context, and I respect that is an important factor in your creations.

 

[harrisonpatm]

I had no idea glass reinforced polymer could be 3d printed. I know of it's qualities at minimum by how long my power tools casing have survived.

Specifically, PA6-GF10 (or 30) is one of the most common used plastics in tools and cases. You don't get all of the same properties when it's extruded out a .4mm nozzle, but you get a lot of the same strength.

 

[harrisonpatm]

Impressions so far: it's awesome!

Mechanically, the bike is so much better than my last frame that I converted. Better suspension, better handling, better braking, more comfortable seat, more comfortable riding position. Fewer wires and cables and other random things that clank around every time I hit a bump. But the better suspension means I've been hitting the same bumps that used to rattle me, but now I barely feel them. Very pleased with this frame.

Electrically, it's so much nicer going up to 105v nominal from 72v nominal. Previously, I could go on major roads in my area. But holding the throttle down all the way only got me to 55MPH or so, nothing more unless I wanted to really drain the battery. Now, on regular (non-boosted) mode, I have the same acceleration, all the way up to 100kph/70mph, on regular mode, only discharging the battery at 1-1.25C, no more. Which is just awesome, and exactly what I wanted out of the build: an overpowered battery that can easily handle speed limits of the roads I travel, with plenty of headroom for shooting ahead of traffic if I want to. I don't plan on ever using the highway. And I'll probably try my "boost" mode at some point and I can report back on a proper 0-60mph or top speed, but it's frankly not important to me.

I've only been on a couple of longer rides, and I've yet to do a proper range test in real world conditions. But if you take my two longer trips that I've made, and assume the range tracks appropriately, I'm looking at a range of 140-160km/85-100m miles. Again, this is awesome for me and meeting the goals of my build.

Disappointingly, my charging station is not turning out the way I had planned. I have a 14s DIY solar powerwall at home, and I was planning on using this to boost my powerwall voltage up to 116.8V. Unfortunately, upon testing an actual charge on the battery, their 900w rating was way way overrated. I expected it a little, thinking that I would only try to pull 500w, and put 4 of them in parallel. But I have 1 so far, and it's maxing out at about 120-140w! Meaning the motorcycle is basically always charging, because my 90ah battery only charges 1.2 amps at a time now. Ugh. I do still have 4 more modules in the mail, and will still go ahead with my plan of putting 4 (or 5) in parallel, to get a better charging setup. But it's certainly putting a hitch in my giddyup, to have this awesome new toy that I want to play with, but being unable to charge it as fast as I could. Fingers crossed.

 

[harrisonpatm]

I've only been on a couple of longer rides, and I've yet to do a proper range test in real world conditions. But if you take my two longer trips that I've made, and assume the range tracks appropriately, I'm looking at a range of 140-160km/85-100m miles. Again, this is awesome for me and meeting the goals of my build.

I was thinking about this. My last bike had an efficiency of 120-140wh/mile. If I were to assume 85 mile range (the low end of my estimation), and my battery has a capacity of 9300wh, that would give the new motorcycle an efficiency of about 110 wh/mile. More efficient. Even though the weight is about the same, I got it weighed yesterday at 368 pounds/167kg. I don't think it's particularly more aerodynamic, is still has a big flat square mass behind the wheel.

So I'm crediting two reasons for the increased efficiency. First, even though the LG MH1 cells I'm using aren't particularly low IR or high drain rated, I'm using so many in parallel that I never draw too many amps from them, meaning less voltage sag, less wasted energy. Second, by increasing the voltage rating of the battery I'm using, but still staying at roughly the same performance/speed, I'm perhaps keeping within the efficient RPM range of my motor, which is typically 80% of it's no-load max speed. Wasn't my intention, but perhaps I just got lucky.

I also made an effort to use thicker, better cabling for my battery amps, so maybe I get a percent or two efficiency gain from that.

 

[jkrienert]

Those specs seem really promising. More so than a lot of production bikes I'm reading about. So cool.

 

[harrisonpatm]

Those specs seem really promising. More so than a lot of production bikes I'm reading about. So cool.

"This one weird trick that the electric motorcycle industry hates!"
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It's tons of free time spent towards labor. That's it, that's the trick.

 

[harrisonpatm]

I rarely, if ever, take videos, so I apologize about the terrible quality. But here's a couple short clips in case anybody is interested.

 

[Buildsix]

I rarely, if ever, take videos, so I apologize about the terrible quality. But here's a couple short clips in case anybody is interested.

Brilliant! This gives me so much motivation to get mine done!