Converting Electric Unicycle into an Ebike

[Rizella]

Hi all,

I've only seen 2 very old posts talking about this subject and I don't know if they got anywhere with it and would like to revisit this subject in more detail.

 

Has anyone or does anyone know exactly how to convert an electric unicycle EUC for use on an bicycle?

 

Reason being is because they are a lot more accessible to me than an ebike and I have been disappointed by the lack of speed and range of ebikes. EUCs seem to have progressed a lot further than ebikes, giving more power and range and I thought of simply converting that onto a bike frame.

 

My thoughts are to remove the motor and tyre together. Strap that to the front/rear of the bike. Strap the batteries and control board to the bike too. Maybe a thumb throttle to control speed.

 

Any special requirements needed?

 

TIA

[Tawpie]

You'll be putting you mad mod skills to the test for sure, mechanical and electrical. It's going to be a very interesting project with some fun challenges!

[meepmeepmayer]

I don't think using a EUC control board makes too much sense. EUCs control their motor only by how the board is tilted.

Not only would your control stick somehow have to tilt the board very precisely (EUCs react to tilts very rapidly). The board would also not be level when you go up or down even a slight incline or decline, leading to unwanted and uncontrollable acceleration or braking. For example, assume the board is mounted to the bike like it is mounted to the EUC. As soon as you start going down a hill, it will accelerate (because the board leans forward) and never stop accelerating (because the lean doesn't go away). So it would uncontrollably catapult you down any hill. And if you started going up a hill, it would brake first (lean backwards) and then rapidly accelerate backwards (lean still there) until you are on the level ground you came from. Doesn't sound very useful

No problem with the motor/battery pack if you find some other board to control the motor (where you control what you want it to do, instead of the lean). Or you mount the EUC board in some self-leveling contraption (it has to work very well, and be fast), and then you can subtly manipulate (tilt) the board to control the motor. That probably won't work in real life.

Maybe the better alternative is to do something like go-karts for hoverboards (it's a frame and you put in the hoverboard as motor/control -  look it up). You could simply replace the front tire of your bicycle with a EUC. Just make the connection via the pedal mounts. Then you only need to figure out some way to control the EUC's tilt, and you're there.

And you get a full, working, non-dissected EUC out of it!

I you don't want to go the EUC route, you can use a EUC motor and battery packs along with some other board to control the motor.

[SereneCry]

I've been thinking about the same thing. But just with a throttle of some sort hooked onto the existing board, maybe disabling the gyro or hooking into the READ/PRINT ports on the board to reprogram it.

EDIT:
I'll take apart my wheel and take pics of where I was thinking the controller could accept inputs from throttle and where the I/O pins are. Probably not so big difference between the various EUC brands on that particular component! They all need those programming pins to test the boards before assembling. The gyro should equate to a throttle to a certain extent.. Just remains to be figured out how much needs modding to insert throttle (potentiometer?) where the gyro was...

Edited March 12, 2021 by SereneCry

[SereneCry]

What about this throttle:

Hooked up to the board according to this: https://content.invisioncic.com/r254450/monthly_2017_06/EUC_labeled_mainboard.thumb.jpg.9d7d7e53ef7550909f74eb606d8e25d6.jpg

At J4. You see the I/O there with the unused pins. And the comport topright (between the red & black plug and the two white plugs).

From this thread

Looks promising!

Edited March 12, 2021 by SereneCry

[Rizella]

I'll be honest with you, it's over my head when it comes to customizing an existing board. I'll be interested if you find a 84v or 100v speed controller. That would be ideal.

[SereneCry]

Plenty of different controllers. Not sure which. KT can be flashed with OpenSource Firmware so you can customize it. Do you have a specific wheel in mind?

I got one on the workbench now, SN: QJ60V350W 141025050. Driverboard almost this https://ibb.co/hDksbTx
I cant afford a new motorcontroller and think its more interesting to make the original work. Preferably so it can still be used as a EUC. Its watertight, got all the components in a small, simple format.

The basics is the following picture, and illustrates what is needed.

But why limit it to just a bike? Ideally something like a EUC could be a drop-in power+drive for any vehicle or appliance. Like a boat, snowblower, lawnmower, twowheeler and fourwheeler. Question is how little modification is needed.
Don't really know what controller.. Maybe this? https://endless-sphere.com/forums/viewtopic.php?f=30&t=87870

Edited March 13, 2021 by SereneCry

[Rizella]

2 hours ago, SereneCry said:

Plenty of different controllers. Not sure which. KT can be flashed with OpenSource Firmware so you can customize it. Do you have a specific wheel in mind?

I got one on the workbench now, SN: QJ60V350W 141025050. Driverboard almost this https://ibb.co/hDksbTx
I cant afford a new motorcontroller and think its more interesting to make the original work. Preferably so it can still be used as a EUC. Its watertight, got all the components in a small, simple format.

The basics is the following picture, and illustrates what is needed.

But why limit it to just a bike? Ideally something like a EUC could be a drop-in power+drive for any vehicle or appliance. Like a boat, snowblower, lawnmower, twowheeler and fourwheeler. Question is how little modification is needed.
Don't really know what controller.. Maybe this? https://endless-sphere.com/forums/viewtopic.php?f=30&t=87870

That's really detailed. I've got a veteran sherman, but could even be a 84v msx. They are fairly inexpensive and have all the components to strip apart and make a bike. 

[SereneCry]

Cool. I got one particular project on hold that parallells yours: Putting a EUC on a moped/MC. If you dont need pedal-assist it would be pretty much the same thing.

I would need moar powerful motor anyway but cant afford a complete EUC, so I'll get a used one with burnt out batteries or something. Just a powerful hubmotor basically. Higher voltage as possible because that takes less amps which means we can have thinner wires. The heat would then be from motor, batteries and controller. This can somewhat be mititgated with heatfins as long as its not california. 

So voltage 84-100V. How many amp?

[SereneCry]

Would this work?
https://www.dhgate.com/product/36v48v60v64v-500w600w-bldc-motor-controller/397229255.html#listing_wordrec-21

[SereneCry]

Found thread on similar topic:

https://endless-sphere.com/forums/viewtopic.php?f=30&t=87870

[OldFartRides]

Have you seen the super monarch and S.M. Crown 2 w.d. E bikes ? They look pretty kick ass to me. I was considering one of those before I pulled the trigger on the euc.

best of luck with the project if you go that route.

[DangerDan]

You can get rdy to install hub motor & controller kits for bikes - why all the hussle to rework a euc?

https://electricbikereport.com/electric-bike-hub-motors-the-complete-guide/

https://hpcbikes.com/products/hub-motor-conversion-kit

 

Edited March 19, 2021 by DangerDan

[Rizella]

14 hours ago, DangerDan said:

You can get rdy to install hub motor & controller kits for bikes - why all the hussle to rework a euc?

https://electricbikereport.com/electric-bike-hub-motors-the-complete-guide/

https://hpcbikes.com/products/hub-motor-conversion-kit

 

Show me a kit that's actually decent specs. I can't fine anything over a 1.5kw motor. Then you still have to find the batteries that will power it. No batteries I've seen are over 72v and even then anything over 48v is hard to come by.

 

Makes sense to just get a controller.

[DangerDan]

the guys in the second link offer kits up to 6kw 

- steep money tho.

Edited March 19, 2021 by DangerDan

[Rizella]

3 hours ago, DangerDan said:

the guys in the second link offer kits up to 6kw 

- steep money tho.

All I need is a 84 or 100v speed controller. Get that and you're golden. Chances of finding one... Slim because ebike technology is so far behind.

 

Look at escooters... Very small wheels and you've got a 2.6kw hub motor in each wheel sometimes. Why can't they do that in ebikes affordably... Around 1k mark? But you just see these rubbish 350w ones going for £4.5k! Ridiculous

[DangerDan]

i think u get a lot things mixed up.

you want a 100v high powered ebike for 1k, have you looked up what a scooter with the specs you have in mind costs?

you get vesc controllers with 100v 250/400a without any problems.
https://trampaboards.com/vesc-100v-250a--22s-c-1697.html

 

Edited March 20, 2021 by DangerDan

[Rizella]

8 hours ago, DangerDan said:

i think u get a lot things mixed up.

you want a 100v high powered ebike for 1k, have you looked up what a scooter with the specs you have in mind costs?

you get vesc controllers with 100v 250/400a without any problems. this took me 2minutes to find...
https://trampaboards.com/vesc-100v-250a--22s-c-1697.html

invest some time and get up to date with the market and options.

Thanks for the link, I couldn't find it but that looks perfect other than the fact it needs programming and isn't just plug and play but still. Cheers

[DangerDan]

a euc controller on the basis of vesc would be dope

Edited March 20, 2021 by DangerDan

[yuweng]

On 3/20/2021 at 7:34 AM, Rizella said:

All I need is a 84 or 100v speed controller. Get that and you're golden. Chances of finding one... Slim because ebike technology is so far behind.

Look at escooters... Very small wheels and you've got a 2.6kw hub motor in each wheel sometimes. Why can't they do that in ebikes affordably... Around 1k mark? But you just see these rubbish 350w ones going for £4.5k! Ridiculous

Mentioned this awhile ago, yeah, its crazy that the whole world mark up like mad for ebikes even in China ! i found out if you order direct to China, look for the term electric scooter/ electric motorcycle - power supply/ controller/ BMS etc & it will only cost a faction of the price, i presume bcos these are mass produce instead of ebikes. Recently i just ordered a 1000watt hub motor from taobao & it only cost about £50 can you believe it ! Unfortunately they don't deliver to the U.K. Having said that, you can try taobao agent or ebay, amazon or aliexpress

16 hours ago, DangerDan said:

a euc controller on the basis of vesc would be dope

It was awhile ago but never got release

[Sirsmok2]

I have a 2500w motor and battery packs from a msp High torque and would like to make it into an e-Bike how would this be done?

[Rizella]

7 hours ago, Sirsmok2 said:

I have a 2500w motor and battery packs from a msp High torque and would like to make it into an e-Bike how would this be done?

From what I understand, you'd need a 100v speed controller. Once you've got that I think you're all set. But I believe they can be pricey! 

 

Would be interesting to know if you go ahead with it

[Molly Friedrich]

I'm doing this now.

 

I originally modified my ks18xl into a one wheel vespa, inspired by the Bel Y Bel one.

 

But the issue was that the KS18xl is so powerful that it was actually over cornering... So I decided to use the motor and battery and drive them with a 90v 3000w KT controller.

 

Everything is going great except for one thing:

 

I'm not entirely sure what to do about battery balancing, and could use some advice.

I removed the king song controller from the case, and have just the batteries and motor in it currently.  But part of the controller is dedicated to balancing and limiting the batteries with fuses, as far as I can tell...  So should I try to replace that, or is it possible to separate that part of the board and just use it?

 

Am I wrong and there's not actually board dedicated to battery balance?

 

M~

 

[Molly Friedrich]

Just a quick addendum to add that I did some research into bms and I'm going to try this one:

 

https://www.amazon.com/3Series-Protection-Li-ion-Battery-Balance/dp/B075MH52JG/ref=trb_chk_auth?dchild=1&keywords=2s+60a+bms+12v&qid=1622896662&sr=8-2-spons&psc=1&smid=A2KRDQ1AI5Y5G6&spLa=ZW5jcnlwdGVkUXVhbGlmaWVyPUExMTlLSDNEWjdISlI4JmVuY3J5cHRlZElkPUEwMzUxNTg4MVMyNUIyOFVFNlk5NCZlbmNyeXB0ZWRBZElkPUEwMDY2MzA4MkE2RkswQ0JBMk5KRyZ3aWRnZXROYW1lPXNwX3Bob25lX3NlYXJjaF9hdGYmYWN0aW9uPWNsaWNrUmVkaXJlY3QmZG9Ob3RMb2dDbGljaz10cnVl&openid.assoc_handle=anywhere_us&openid.claimed_id=https%3A%2F%2Fwww.amazon.com%2Fap%2Fid%2Famzn1.account.AFVKTVM2MRT4HZZYXH5X66J564KA&openid.identity=https%3A%2F%2Fwww.amazon.com%2Fap%2Fid%2Famzn1.account.AFVKTVM2MRT4HZZYXH5X66J564KA&openid.mode=id_res&openid.ns=http%3A%2F%2Fspecs.openid.net%2Fauth%2F2.0&openid.op_endpoint=https%3A%2F%2Fwww.amazon.com%2Fap%2Fsignin&openid.response_nonce=2021-06-05T12%3A40%3A49Z-4443218038338528201&openid.return_to=https%3A%2F%2Fwww.amazon.com%2F3Series-Protection-Li-ion-Battery-Balance%2Fdp%2FB075MH52JG%2Fref%3Dtrb_chk_auth%3Fdchild%3D1%26keywords%3D2s%2B60a%2Bbms%2B12v%26qid%3D1622896662%26sr%3D8-2-spons%26psc%3D1%26smid%3DA2KRDQ1AI5Y5G6%26spLa%3DZW5jcnlwdGVkUXVhbGlmaWVyPUExMTlLSDNEWjdISlI4JmVuY3J5cHRlZElkPUEwMzUxNTg4MVMyNUIyOFVFNlk5NCZlbmNyeXB0ZWRBZElkPUEwMDY2MzA4MkE2RkswQ0JBMk5KRyZ3aWRnZXROYW1lPXNwX3Bob25lX3NlYXJjaF9hdGYmYWN0aW9uPWNsaWNrUmVkaXJlY3QmZG9Ob3RMb2dDbGljaz10cnVl%26trb_auth%3D1%26trb_open%3D1%26trb_bid%3Dbuy-now-button&openid.signed=assoc_handle%2Cclaimed_id%2Cidentity%2Cmode%2Cns%2Cop_endpoint%2Cresponse_nonce%2Creturn_to%2Cns.pape%2Cpape.auth_policies%2Cpape.auth_time%2Csigned&openid.ns.pape=http%3A%2F%2Fspecs.openid.net%2Fextensions%2Fpape%2F1.0&openid.pape.auth_policies=AmazonMultifactor&openid.pape.auth_time=2021-06-05T12%3A40%3A48Z&openid.sig=6TPnTa%2BkzOoTAxqqc9lkYlwWAvFjDgx7Pq23MCpMoqs%3D&serial=&

 

After looking at how they are wired, I believe I can use this one as a 2s as long as I wire them in order properly.

So this will hopefully be my trikes' balancer and charge protector!

[OldFartRides]

3 hours ago, Molly Friedrich said:

 

.... inspired by the Bel Y Bel one.

 

 

 

https://www.belybel.com/creations/monowheel-z-one/
Had not seen that. Pretty.