First post, electric motorcycle build.

General Discussion about large electric scooters and motorcycles and other things with no pedals.
phate   10 W

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Re: First post, electric motorcycle build.

Post by phate » Jun 14 2018 8:13pm

spectastic wrote:
Jun 14 2018 5:39pm
what if the two motors out put aren't exactly the same? wouldn't the motor doing less work slow down the motor doing more work?

what's the reasoning to have 2 motors instead of one?
I've gotten this question a bit. They're identical motors running identical controllers, so they should be reasonably close.

But even if they aren't the same: Both motors are putting work into a shared geartrain (so they're spinning at the same speed at all times) and they're running on separate controllers that aren't even aware of each other. All the controller is ever going to see is "I'm spinning ___ rpm, and the throttle is asking for more power". One might put slightly more work into moving the bike than the other, but they're both putting work in so they'll never really end up fighting each other.

Running two motors allows me to use smaller outrunners that were easier to drive without spending too much on a controller. I'm more comfortable with things that resemble RC stuff, so that's kinda where things went. Also the power density for how small/light these are is pretty insane.

Updates:

Picking up my donor bike tomorrow afternoon. It's a 1995 Kawasaki Ninja 500 that threw the chain and cracked the crankcase. $400 sporty standard with clean paperwork and needs an engine, can't really complain.

Gathered some more parts as well. My motors are in the mail, but my contactor, meanwell's, DC-DC converter, and one of the two kelly controllers are here. I only ordered one of them for now, and I'll grab the other one once I verify that they will run these motors properly. Still waiting on my BMS, gauges, and some other goodies, but once the motors are here I've got all the big stuff at least.

Once I have the bike here I can finally strip it down and get some real measurements off the frame to make the final motor mount and battery pack housing.

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Re: First post, electric motorcycle build.

Post by spectastic » Jun 14 2018 11:12pm

phate wrote:
Jun 14 2018 8:13pm
spectastic wrote:
Jun 14 2018 5:39pm
what if the two motors out put aren't exactly the same? wouldn't the motor doing less work slow down the motor doing more work?

what's the reasoning to have 2 motors instead of one?
I've gotten this question a bit. They're identical motors running identical controllers, so they should be reasonably close.

But even if they aren't the same: Both motors are putting work into a shared geartrain (so they're spinning at the same speed at all times) and they're running on separate controllers that aren't even aware of each other. All the controller is ever going to see is "I'm spinning ___ rpm, and the throttle is asking for more power". One might put slightly more work into moving the bike than the other, but they're both putting work in so they'll never really end up fighting each other.

Running two motors allows me to use smaller outrunners that were easier to drive without spending too much on a controller. I'm more comfortable with things that resemble RC stuff, so that's kinda where things went. Also the power density for how small/light these are is pretty insane.

Updates:

Picking up my donor bike tomorrow afternoon. It's a 1995 Kawasaki Ninja 500 that threw the chain and cracked the crankcase. $400 sporty standard with clean paperwork and needs an engine, can't really complain.

Gathered some more parts as well. My motors are in the mail, but my contactor, meanwell's, DC-DC converter, and one of the two kelly controllers are here. I only ordered one of them for now, and I'll grab the other one once I verify that they will run these motors properly. Still waiting on my BMS, gauges, and some other goodies, but once the motors are here I've got all the big stuff at least.

Once I have the bike here I can finally strip it down and get some real measurements off the frame to make the final motor mount and battery pack housing.
in an ideal world, yes, you would expect that 2 things having the same input would have the same output. but the engineer and builder in me thinks otherwise. there's a documentary on when they started racing electric bikes at the isle of man tt (i think it's called "Charge"). the first prototype of the team the doc was covering had endless issues with the battery not giving them the range they were expecting, and burnt out motors, and the cause of these issues turned out to be the issue that i was describing. granted, those bikes are going 200 mph, and the problem is sure to be multiplied at higher amps, but i think it should be a concern none the less. two motors can be putting the same work into the same drive train. but if one motor is doing even a little bit more than the other, than the delta in the work done between the two motors is work that is lost. but then again, the tesla cars have multiple motors, and even 4x drive as an upgrade option. i would guess that they're monitoring the shit out of the motors and batteries to keep the car running for as long as they can, but it would take someone with much better knowledge than me to really understand it.

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Re: First post, electric motorcycle build.

Post by flippy » Jun 15 2018 12:30am

if both controllers are matched in their settings it cannot make a difference. personally i am a fan of slighty rotating one motor to offset the dead spot of the magnets, especailly on DC motors.
if you have both motors running on the same axel and same location they both give power at the exact moment as the other one does. making a offset in the middele of the magnets/coils makes for much smoother power delivery and also helps each motor to deliver power in their own . this is really important on chain drives. if you have a single 6 phase motor you dont have a choice but with separate motors it is something to keep into account.
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Re: First post, electric motorcycle build.

Post by phate » Jun 15 2018 8:18am

Even if for some reason one motor were to put drag on the other, the motor/controller that is working harder would not see that any differently than if I was going up a hill. Both controllers are current limited, so it's not like I'm going to magically start pulling a ton more amps. I'm not worried about them working against each other.

Flippy, I had considered offsetting each motor slightly to get smoother power delivery, but then again they're both 24 pole motors geared around 4:1, so it's gonna spin pretty smoothly. Depends how easily I can clock them relative to each other though, I might do it anyways.

After doing a bunch more research on the undefeatable Kelly soft-start issue, I'm glad I have a dual motor/dual controller setup, because on a single controller the soft start would be pretty weak, but with two of them it should still feel pretty good coming off the line.

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Re: First post, electric motorcycle build.

Post by macribs » Jun 15 2018 9:21am

es member recumpence has done both dual and triple motors and possible a quad motor bike as well if that was ever completed.
He uses rc style esc hv 160 from castle and astro 3220 motors @7-10 000 rpm. Don't think he ever had any sync issues and he taps all the power possible from those motors. I think I had peak power of 28 kw of one of his dual motor bikes. Several others here has done dual motors without any issues to syncing.

I don't think sync is really a problem. If it was I am sure we would have heard about it.

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Re: First post, electric motorcycle build.

Post by phate » Jun 15 2018 9:49am

macribs wrote:
Jun 15 2018 9:21am
es member recumpence has done both dual and triple motors and possible a quad motor bike as well if that was ever completed.
He uses rc style esc hv 160 from castle and astro 3220 motors @7-10 000 rpm. Don't think he ever had any sync issues and he taps all the power possible from those motors. I think I had peak power of 28 kw of one of his dual motor bikes. Several others here has done dual motors without any issues to syncing.

I don't think sync is really a problem. If it was I am sure we would have heard about it.
Since they're independently controlled, there's no actual reason to "sync" them, and since they're on a common shaft there's no way they'll try to run at different speeds.

As long as neither motor runs out of puff before the other one does, at any given speed they're both going to be helping to put more torque into the shaft. Even if I had one motor running at 300A and the other running at 100A, obviously the 300A motor is gonna get hotter, but it's still going to be helped by the 100A motor.

If you screwed up and didn't set the throttle settings the same way, yeah you could totally cause a problem if one motor is trying to regen while the other is trying to apply power, but that's about the only way I can think of.

Expect pics of the donor bike later today, and once I clear a bit more space in my garage I can begin my teardown and start mocking up component locations.

Sidenote: Kelly KLS7230S's are way smaller than I thought they were. Absolutely ebike size hardware, not necessarily motorcycle size hardware, but they're one of the only high-commutation speed controllers in that price bracket so if you're a silly person that wants to make things work with 24 pole motors you don't have many options.

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Re: First post, electric motorcycle build.

Post by phate » Jun 15 2018 10:21pm

Picked up my donor today!

1995 Ninja 500. Tires are pretty good, aside from the chicken strip on the rear tire. Brakes are great. Way cleaner than I was expecting, no complaints for $400. It's absolutely fallen over a few times, but it's never been dropped at speed. Engine doesn't hold oil anymore (threw the chain and punched a hole in the case), but it does run and has some aftermarket goodies that I can sell (like the Vance & Hines full exhaust)
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It's going to live under my porch for a few more days until I put new fuel lines in my accord and get it out of the garage again.

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Re: First post, electric motorcycle build.

Post by macribs » Jun 16 2018 1:51am

Nice donor. Looks clean from the pic. Can't remember how those bike looked when new, but I seem to recall they had a little bit more fairing on the lower side and underbelly? Or was that the bigger brothers maybe? The Ninja 500 had a semi enclosed frame and motor maybe, missing only the underbellypan?

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Re: First post, electric motorcycle build.

Post by phate » Jun 16 2018 9:21am

macribs wrote:
Jun 16 2018 1:51am
Nice donor. Looks clean from the pic. Can't remember how those bike looked when new, but I seem to recall they had a little bit more fairing on the lower side and underbelly? Or was that the bigger brothers maybe? The Ninja 500 had a semi enclosed frame and motor maybe, missing only the underbellypan?
They were available with or without the lower fairing. Because Kawasaki sold boatloads of them and didn't really change anything for like 20 years on this bike, you can get set up with a complete aftermarket low fairing for under $200 shipped, which is what I am going to do.

There were are few different fairing styles out there, I think this was the stock one:
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Most of the aftermarket ones go for full coverage, which is what I want:
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The dent in the tank is going to be easy to fix since I'm going to cut the bottom of it out - I'll just hammer the dent back out from inside.

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Re: First post, electric motorcycle build.

Post by macribs » Jun 16 2018 1:26pm

That full fairing is nice. Good choice, and less drag. Will look clean too.

Have anything planned for the subframe and seating? If you get that new full fairing your bike could look a lot newer if you do something to the subframe/seating that could be your winter project. Now you need to get it up and running so you get to enjoy the electric bike as much as possible before winter hits.

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Re: First post, electric motorcycle build.

Post by phate » Jun 16 2018 4:15pm

Honestly I love the seat that's on it. It's kind of a formless blob but oh man is it comfy.

If I had to guess, the final appearance is pretty much gonna look like the blue bike in the above post, minus the exhaust.

I'm going to be leaning on the original engine cradle to mount basically everything as low as I can. Stock radiator is going to be flushed out and to cool the motors (and controllers if I find a cold plate to fit them).

I'm going to start stripping it in the next week so I can get some real measurements off of it to determine what the driveline actually needs to look like, and whether or not the frame is wide enough for me to be able to get away with running the single shaft or if I'll have to just chain the motors together.

Probably also going to join an EX500 forum to unload stuff like the carburetors, exhaust, starter, etc.

I expect to have it running before the end of the summer, but I probably won't be commuting on it until next year.

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Re: First post, electric motorcycle build.

Post by phate » Jun 23 2018 4:37pm

Updates!

Motors and 1 of the 2 Kelly KLS controllers arrived!

KLS 7230S's are T I N Y. I only bought one because I wasn't sure how well I'd be able to spin my motors with it. Once I can prove on the bench that the motor runs well, I'll pick up the second controller. LG HE2 for scale.
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I decided that I really prefer the stock throttle/grip setup on the bike to any of the twist throttles I've seen, so I'm going to try to just use a Honda TPS with the stock cable throttle. Just about any controller will take a 0-5v throttle input, which is what a honda TPS will do. I can get an entire working throttle body assembly from a 90's civic for free, which already has a throttle rotor/arm, TPS, and multiple mounting holes on it. I figure I can probably just hack off any chunks of aluminum I don't need, bolt what's left to the frame, and I'll have an extremely stout throttle setup that will be more reliable than any other component on the bike.

FRC Hobby/Alienpower/Epowerhobby outrunners are not tiny.
Here's one of the two 120100 sensored watercooled outrunners I'll be running. Do many poles! They have a much longer stator than the 12090's I was originally looking at, and didn't cost much more in the scheme of this project, so it seemed like a no-brainer. It's 50kV, rated for up to 100V/350A, and weighs about 9lbs. With the water cooled stator, I don't see any reason not to just monitor stator/winding temps and chuck current at them until I start to get worried, so I've got plenty of performance headroom once I decide to move away from the tiny KLS controllers.
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I also did some more design work on the battery pack, and finally nailed down how I'd like to connect the cells themselves. Rather than bolting the cells together, which is absolutely insane to try to do with more than 12 cells, I'm just going to have some copper plates waterjetted. Yeah, it costs money, but will work a million times better than anything that I have the fabrication ability to do at home. Straighten all tabs, stack cells evenly (here's where 3d printed spacers/guides come in handy) and stick together with 3M tape, insert 4 positive tabs through slots in plate, fold positive tabs over and secure to plates (probably just going to tap some holes and secure them with a short bolt/washer, which would also be used for cell-level voltage taps for the BMS), then repeat with 4 negative tabs in the remaining 4 holes.
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After that it's probably just going to be a mix of 3d printed spacers to locate the cells within the battery pack, and a case to provide a mounting point for everything. Think "2020 aluminum extrusion kicking around from 3d printer upgrades with plastic side panels".

Also, I got my crapbox/race car out of the garage, so now I actually have room to work on the bike.
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It's a 97 accord sedan with only ~165hp but way too many goodies in the suspension. Basically worthless, so I'm not afraid to do have fun with it. If I break something, I'll just fix it. I'll have to see if I can find the cad models and parts list from when I was at school, I have a hydraulic rear sway bar drawn up for this thing, among other terrible ideas.

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Re: First post, electric motorcycle build.

Post by phate » Jun 27 2018 1:09am

Attempted to bench-test the motor and controller. Threw together a quick and dirty 7S lipo pack just to get things to power up, got the motor, halls, contactor with precharge resistor, and a cheap scooter throttle connected.

Was tripping the contactor with a portable jumper pack.

I'm going to blame what happened next on a combination of sleep deprivation (I work overnights, and I wanted to get the motor to spin before I went to bed, so I was probably doing this at around 3pm aka my bed time) and less-than-optimal work lighting, but you'd be amazed to hear that thin red wires and thin pink wires look awfully similar under the right/wrong lighting.

Because of that mix up, I mistakenly connected ~26v DC positive to what was supposed to be the +12v output from the controller. There was a spark, the controller lit up for a second, then shut off. I noticed that I mixed up those two wires, corrected the issue, and now I can get the controller to power up and stay on but I'm getting Angle Sensor error codes (3 blinks, 4 blinks) and am unable to talk to it via RS232.

Verified that I have a 5V across power and ground of the hall board, so that's at least getting juice still. For some reason I forgot to check if I still even have anything from the controller's 12V supply, but I'm assuming I blew up some part of the 12V regulator, which likely took out the RS-232 comms, and can hopefully be fixed by putting a new capacitor/diode in the spot the likely has a scorch mark. Also going to try to get the serial connection to work using another computer.

Well aware that posting that here means that I blew any warranty/chance of getting the thing fixed, but I'm going to own what was likely a $220 mistake. Ordered another one. If these controllers will actually work on my bike, I needed two of them anyways, and I'll be able to use my not-blown-up controller as a reference to figure out what to replace.



Also started playing around with another variation on the primary drive, which I like a lot more for several reasons (aside from the fact I could just make the entire thing on a drill press). I'll need to add some more detail to the motor model, but assuming I can still get to the water cooling barbs, I should be able to just grab a chunk of 6in x 2in aluminum box tubing. Can definitely do it if I use 6 x 3 tube.

The primary chain has a 1.5:1 ratio, which is enough to allow me to use stock sprockets to get about where I want it. As far as I can tell, a rear sprocket for a 1990-1995 ZX600 (probably more years than that actually) should fit on the bike (same 6 on 130mm bolt pattern and 110mm center bore) and allow me to run a 530 chain instead of the stock 520. Yeah, 530 is heavier, but with a 530 chain I can just use a keyed front sprocket from Mcmaster (or Tractor Supply, or Grainger, etc) because it's the exact same size as #50 industrial chain. Probably going to run a 45T rear sprocket and a 16 or 17 up front to hit my target 4:1 gear ratio.

All-in, the entire power unit (aluminum case, both motors, all the bearing blocks, shafts, sprockets, etc) will end up around 30lbs, which is right around the weight a motenergy etek-that-isn't-an-etek, with (hopefully) a lot more power. Aside from a bunch of additional holes and slots being cut in the aluminum that are necessary to do things like install/tension a chain, there's a ton that I could do to make this a lot lighter (aluminum bearing blocks instead of cast iron, aluminum sprockets, etc).

The countershaft section is narrow enough that I should have no problem fitting it on just about any frame with near-stock sprocket location, and the #40 primary drive chain is nice and short but well within the accepted working loads.
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Re: First post, electric motorcycle build.

Post by 81forest » Jun 27 2018 9:44am

Wow, nice progress. Bummer about the wiring mix up. :cry:

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Re: First post, electric motorcycle build.

Post by phate » Jun 27 2018 11:11am

My smart BMS showed up, so that's pretty cool as well. Grabbed one of the 300A smart bluetooth ones off aliexpress. It can apparently do up to 24s, which is cool. There are a few cells that look a bit beat up, so if those end up being problematic during testing I'll scoop a few more to replace them, and might either go to 21s or 22s (charged to 4v/cell) while I'm in there.

Since both the BMS and my coulomb meter have screens but lack a housing, I'll probably end up 3d printing a case for both of them (and obviously sharing the files on thingiverse for anybody who wants them). I grabbed the coulomb meter because unless I can configure the BMS to correctly read a 750A shunt, I won't be able to get a reading if I actually start leaning on the pack.
81forest wrote:
Jun 27 2018 9:44am
Wow, nice progress. Bummer about the wiring mix up. :cry:
Yeah I'm pretty annoyed about that. A few of the EE's I work with offered to take a look, and having a non-blown-up controller to compare against will probably help. I'm a Mech E that's okay with electronics (although not necessarily all that great at differentiating between pink and red when I'm tired), so aside from following obviously visible traces or locating a scorch mark that was once a component (and soldering in a new one if I can figure out was it was) I'm not especially useful once you get to the circuit board level.

I figure absolute worst case I managed to totally smoke the low-power side of the controller, and I keep it around to eventually hack the case/heatsink and power stage into something useful.

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Re: First post, electric motorcycle build.

Post by flippy » Jun 27 2018 2:11pm

If you can put up a panel version and a stand alone housing for that smart bms lcd i would be very grateful. I am looking for such a thing for months now because i cant cad draw to save my life.
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Re: First post, electric motorcycle build.

Post by phate » Jun 27 2018 3:05pm

flippy wrote:
Jun 27 2018 2:11pm
If you can put up a panel version and a stand alone housing for that smart bms lcd i would be very grateful. I am looking for such a thing for months now because i cant cad draw to save my life.
Of course! Need to finish putting the new stepper drivers in to get the thing moving again (old drivers got angry when I added a second extruder), but once I have it printing again I'll knock out some prototypes.

What sort of housings did you have in mind? I was going to start with a simple box around it with some M3 holes in the back so you can use whatever you want to secure it.

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Re: First post, electric motorcycle build.

Post by flippy » Jun 28 2018 12:20am

phate wrote:
Jun 27 2018 3:05pm
Of course! Need to finish putting the new stepper drivers in to get the thing moving again (old drivers got angry when I added a second extruder), but once I have it printing again I'll knock out some prototypes.
What sort of housings did you have in mind? I was going to start with a simple box around it with some M3 holes in the back so you can use whatever you want to secure it.
such a houding would be fine, personally i use M5 a lot because its much less annoying to use, stronger and simpler to print.
i am mostly interested in a flat panel design that i can put a thin piece of acrylic in as glass and mount the lcd as a replacement dashboard on scooters and stuff.
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Re: First post, electric motorcycle build.

Post by phate » Jun 28 2018 8:19am

I can use M5 hardware just as easily, lol. I have a ton of M3 stuff around from when I built my printer, so instead of modeling/printing the threads all I usually do is print a 2.5-ish mm pilot hole and run through it with a tap. There's probably an M5 tap in the box as well.

Either way, whether it's a flat plate with cutouts and mounting holes for the screen, or an actual box to go around everything, I'll include some way to put a piece of plexi over the top. Might model that (but not print it) this afternoon.

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Re: First post, electric motorcycle build.

Post by John in CR » Jun 30 2018 11:23am

Using a the stock cable pull throttle and a cheap but reliable TPS sounds like a great idea. Please be sure to share all the details, so even those of us still in the stone age regarding electronics can copy your solution. Most of my motors require 2 controllers, so I'll be especially interested in issues related to your application.

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Re: First post, electric motorcycle build.

Post by phate » Jul 07 2018 12:25pm

Found a couple cells I wasn't quite comfortable putting on the bike, so I bought 8 more of them. Reconfiguring the pack to 21s4p, which is just within the capability of the meanwells if I crank them all the way up.

Second controller arrived, and I popped open the one I blew up. Haven't spotted any scorch marks or anything obviously trashed yet, so I might slap it back together and verify that I've got power coming off the 5v and 12v rails. In other news: I'm pretty sure I can water cool these things pretty effectively with cheap universal PC water cooling parts off ebay.

Construction is pretty interesting. It's spread across two boards. One has what is obviously the "brain" side of things, and looks an awful lot like a standalone 12-Fet controller. The second board has another 18 fets on it. The power connections are split between the two boards, and the output phases are tied together as well. There are a bunch of connections between the legs of the fets between the two boards. As far as I can tell they're just parallel'd together.

There's a big glob of silicone that's probably covering whatever component I popped. I'm gonna put it back together and try to get it to talk to my laptop, and failing that I'm pretty sure my server has an actual serial port on it.

I would not be remotely surprised if Kelly sells the brain board by itself as its own smaller KLS-S controller.

What you get when you pull it out of the case and clean up all the thermal compound.
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Not-at-all useful shot of the brain board. I need to do some more digging here.
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Unfortunately I just had a pretty big shift in priorities. Yesterday the turbocharger went in my Subaru, and potentially took the bottom end with it if it sent metal into the oil pan. Fortunately, I already have the majority of the parts for the bike purchased, but over the next week I'm going to find out if that's going to cost me a few hundred dollars or a few thousand dollars.
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Re: First post, electric motorcycle build.

Post by flippy » Jul 07 2018 12:37pm

I have to look but prehaps i still have a brain box or a powwr supply (5 and 12) board on it.

The 5v supply chip is based on the "led side" on a daughterboard with a fuckton of connection on it. Its the one in the corner.
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Re: First post, electric motorcycle build.

Post by phate » Jul 07 2018 12:51pm

flippy wrote:
Jul 07 2018 12:37pm
I have to look but prehaps i still have a brain box or a powwr supply (5 and 12) board on it.

The 5v supply chip is based on the "led side" on a daughterboard with a fuckton of connection on it. Its the one in the corner.
Yeah, that's visible in the bottom right of the second image. I haven't gotten all the white silicone off, but I'd imagine that's the first thing that would pop when you dump like 30 volts into the wrong place. I wanted to try to poke around between the connector that I unplugged and that board to get a better idea of what goes where.

As I've mentioned, I'm really the wrong kind of engineer for this kind of stuff, lol.

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Re: First post, electric motorcycle build.

Post by phate » Jul 10 2018 10:18am

Did some re-working on the battery pack, and more or less sorted out the case that's going around it. The model looks a bit messy because I didn't feel like re-modeling the cells with the tabs and crimps folded over. Because of this, I can probably pull another inch or so off the width of the case, and about half an inch or so out of the depth depending on how much clearance I want to have on the terminals. Probably have half an inch, maybe a full inch I can pull out of the height as well. I made a few assumptions about the cell spacing

Haven't fully decided if I'm going to add another brace in the middle or not, but once I factor in the fasteners that will be used to bolt the tabs down to the plates, the entire assembly should end up right around 60lbs. Which is heavy for sure, but considering my drive unit is going to weigh about 30lbs, and the controllers only weigh about 4lbs each even with the added heatsinks I think I'm doing pretty well. That's a lot of power in a reasonably compact ~100lb package. Sub-120 if you want to count the charging system and whatnot.

2020 Aluminum T-slot extrusion frame (same stuff my 3d printer is made of), waterjetted aluminum plates to connect the cells together, and 3mm polycarbonate panels retained by 3d printed brackets.

Complete pack assembly. Dimensions are 282mm (11.1in) wide X 214mm (8.4in) deep X 405mm (16in tall). Making it smaller didn't really make much difference in the weight because the aluminum extrusion weighs basically nothing.
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Arrangement of connecting plates. Going to 21s made things a bit interesting.
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Close up showing terminal arrangement on plates.:
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Not at all the final orientation of various components, but here's the pack, drive unit, and controllers (which will likely end up hanging under the frame) mocked up to see how much space I'm dealing with. Not pictured: scattershield to prevent a snapped primary chain from tearing a hole into the battery pack. 16in tall and about 20in long. Drive unit can and probably will be shortened. Pretty sure if you tipped the pack on its side it would fit very nicely into the frame of a 4 cylinder bike.

It's probably not going to fit as laid out, but as you can see I've got tons of vertical room to play with.
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flippy   10 kW

10 kW
Posts: 851
Joined: Aug 12 2015 3:07pm

Re: First post, electric motorcycle build.

Post by flippy » Jul 10 2018 4:07pm

very nice.

are you not going to put anything to insulate the pouches from each other? just to prevent 1 pouch from going "off script" and taking out the entire pack...

some 0.5mil alu plate would do the trick.
Lithium beats liquid dinosaurs.

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