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Discussion Starter · #1 ·
Hi, new member here, have read quite a few threads here to know a dislike for hub motors, but I have an oddball build planned that hub motors would be far preferable for so wanted to see if anyone had any real experience with QS motors in hub motors?

http://www.cnqsmotor.com/en/article...version Kits, 2X8000W Hub Motor Kits/567.html

I see that a startup in Czech Republic is using them for an EV sports car, they're called Luka EV.

I'm in Canada but have an odd import from Japan, a 96' Subaru Domingo, microvan, and intend to convert it to EV, still probably 2 years down the road. Because they're AWD, and due to age and the fact they were never sold in North America parts are; hard to get, slow to get, and cost way more than they are worth, I am planning to take engine and trans out and go with 4 in hub motors. The engine in these little vans are only around 60HP, 900kg with engine/trans. 4 x 8000w hub motors (each 12.5kw continous rated and suited for 1150kg) is the plan at this point.

So, has anyone actually worked with their motors that can give any feedback?
 

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hi bluerain, I am not sure hub motors are a good fit. even though it is only 60hp it looks like it is geared down a whole lot. I don't see them holding up to this sort of abuse https://www.youtube.com/watch?v=bmNQgZUEGks

you will note that in their model car, the luka, they avoid any clips that demonstrate acceleration.

out of 10 minutes of blather there are a couple seconds of it crawling around the parking lot. https://youtu.be/t7sQpaHtqJc?t=522

same with this, any acceleration points are cutscene, though I chose this mark for entertainment reasons :)

https://youtu.be/5U2UX_xcYIc?t=267

but you are of course welcome to try. You pays your money, you takes your chances as they say.
 

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Discussion Starter · #3 ·
I don't really see negatives in the video, that was their first build, the production line in both LHD and RHD models are expected soon. But the question isn't about the car, it was just an example of the hub motors being adopted by that company for production of their EV line. In Canada the Domingo's are a rare import, but used for regular street driving - not crazy offroading. The 4wd is just desirable for when we get snow, they handle nicely.

It's not meant as a debate about hub motor vs other EV motors. I was just wondering if anyone had any experience with them. I realize that lots of people here are entirely against hub motors, but I was hoping there may be some people who had actually tried them in a project. I know their motorcycle hub performed quite well.

I guess if you've driven a Sambar or Domingo you'd know that performance isn't their strength, they are on par with not speedy EV's. They are handy for utility, and the reason I'm keeping mine around is because people love the thing (I mean, they look like a toy van), it gets loads of looks so I'm wrapping it for my business.
 

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you are welcome... w/4 motors you will have 1000 ft pounds at the road, the (not loaded down with heavy batteries) Domingo "appears" to have a lot more than that, while not being able to go very fast (only 60hp). if the luka had some decent torque, they would show it. plus motors in puddles and bouncing around.
 

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Discussion Starter · #5 ·
It's seemingly lose - lose.

Hubs have their downsides, but doing a normal conversion on this does too. To keep 4wd on the normal conversion I need to keep transmission etc, which sets up for the long and costly repair when parts of that system go.
 

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do you happen to know the gear ratios (the axle ratios? and the transmission ratios? and the transfer case?) It *might* help the long term maintenance prospects to get the automatic (or manual) out of the picture. you might be able to remove the transfer case as well with 2 motors. but we need a more specific idea how much wheel torque it currently makes with that 60hp so as to set post conversion performance expectations. If you have the ratios I would be interested in them.

edit did find this, does it apply? transfer case change anything?
http://www.goo-net-exchange.com/catalog/SUBARU__DOMINGO/4502161/

5.8 rear, first is 3:1, 5th is 0.69 and the stock motor makes 70ft lbs. Maximum Power 52ps(38kW)/4800rpm Maximum Torque 9.7kg・m(95.1N・m)/3200rpm

assuming tires are 12" radius, or close enough.

to match that peak torque, you are looking at 1218 ft pounds of wheel torque, which isn't that far off of 4x of those hub motors (about 1000 ft lbs iirc , but there are other considerations there).

without the trans, you just have 5.8:1, but can have one motor driving front and one driving rear, so two motors that can make 120 ft lbs each, entirely plausible.

edit: with that tire size and 5.8 ratio you would need about 6000 motor rpm to keep a 70mph top speed, again entirely plausible.
 

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Discussion Starter · #7 ·
That's the right specs for this engine. I'm trying to make this as simple a conversion as possible. Messing with the axles and doing 2 motors will up costs (I don't have a place to work on the rip out and install, so will have to have my mechanic do that at his shop). If I'm not doing hub motors I'd just do one motor and keep existing manual transmission and drive train intact.

If by the time I'm going to do the conversion, the hubs had a higher ip rating g (currently ip54) then I'd probably opt for them. If going one motor, do you have a suggestion on that? Highway speeds around 110km here, and we do have some fairly steep hills.
 

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you are gonna want a real place to work on this, probably even with hub motors.
You gotta rip out all kinds of stuff (motor/driveline bits/gas tank/make room for the battery, possibly beef up the suspension for the extra weight, wiring, controllers etc). it isn't going to be "cheap", the motors are often the least expensive part.

If you are keeping the transmission (manual, yes?) then you don't need as much torque from your motor to get back to where you are now on acceleration and hill climbing. a netgain warp 7 motor and a 500 amp/144v controller would work fine, better than stock. edit: but a caveat, it takes some skills to fabricate and wire everything up.
 

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Discussion Starter · #9 ·
For these, it needs to go up on lift to rip out the engine, other parts can be removed just sitting in a parking space. I'd just simply prefer to keep the transmission and drivetrain intact if I'm forced to go with a single engine instead of hubs.

The electrical portion I'm not worried about doing, I've converted my houseboat to solar for instance, putting 1000 watts of solar, running 100volts into mppt controller, 3kw inverter/charger wired to battery default (so it will only use shorepower if batteries hit a threshold). It's just wanting to minimalize the mechanical changes where possible in this conversion.
 

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Discussion Starter · #10 ·
Still on this topic.

It seems like the Luka is getting close to public sales of their 4 hub motor production car.
http://mwmotors.cz/luka-ev/

And Nikola motors is producing a high performance offroad vehicle, with 4 hub motors... which the US military is testing.

https://nikolamotor.com/reserve/nzt

https://www.designboom.com/technology/nikola-nzt-off-roader-electric-utv-12-21-2017/

https://electrek.co/2018/03/26/marines-test-all-electric-nikola-utv/


So I'm not sure if hub motors are a dead end.
 

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Discussion Starter · #12 ·
Ripperton can answer , he modified them so they are at least functional

Don’t expect to use the motors in the hubs though, His Lira conversion is a good example
Yeah, I see about 6 years ago he did that. Not sure which gen the hub motors he had were. I know they're on V3 currently.

The Luka is using 4 x V3 12.5kw hub motors - in wheel.

The Nikola NZT is also using 4 hub motors - in wheel, albeit their own really powerful ones.
 

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V1 or V100000
You can’t change physics

That said if I could bolt a single ; double shaft 144volt hub motor to one of the front wheels & half shaft on my fwd Honda Insight and have the bearings last more than a month it might be usable since my motor could fire to launch to enough speed that the hub would have enough torque to maintain speed.

Sadly that’s a phantasy, they show scooters with hub motors for a reason, in the hundred years hub motors have been around only a very small number of car prototypes have been produced.

http://www.cnqsmotor.com/en/article...C Gearless Electric Wheel Hub Motors/569.html

There are reasons that only one person in this group has used a heavily modified hub motor for a small car.
 

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Discussion Starter · #14 ·
V1 or V100000
You can’t change physics

That said if I could bolt a single ; double shaft 144volt hub motor to one of the front wheels & half shaft on my fwd Honda Insight and have the bearings last more than a month it might be usable since my motor could fire to launch to enough speed that the hub would have enough torque to maintain speed.

Sadly that’s a phantasy, they show scooters with hub motors for a reason, in the hundred years hub motors have been around only a very small number of car prototypes have been produced.

http://www.cnqsmotor.com/en/article...C Gearless Electric Wheel Hub Motors/569.html

There are reasons that only one person in this group has used a heavily modified hub motor for a small car.
It certainly seems like the Luka is beyond prototype and moving into production (have you looked at their site?), and while it's performance is nothing to write home about, it's better than the Domingo I am working towards converting (though the Luka is far more aerodynamic and about 100kg lighter).
 

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Since we’re on the product that’s always been in production but not used commercially kick here is another more promising hub motor

https://insideevs.com/new-ring-drive-in-wheel-ev-motor-claimed-to-be-a-breakthrough/
Orbis
This "ring" scheme is fundamentally unrelated to a hub motor; some examples shown are not even driven wheels. It can include a drive motor, driving one of the rollers, which is how the "hub motor" connection comes in. Perhaps more importantly, the whole ring-on-rollers scheme (which is popular in "hubless wheel" concept vehicles, especially motorcycles and usually existing only in computer-generated models) has huge practical problems, without bringing any significant benefit over a sensible hub and wheel... but it looks cool! :rolleyes:

The site is full of claims of lower rotational inertia (which is valid, although the improvement in rotational inertia is questionable and rotational inertia is of relatively little importance) but more disturbingly claims of lower unsprung mass which ignore the huge mass of all of the non-rotating components bouncing up and down with the wheel. That demo unit on the Honda is a real mess.
 

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hello, i am planning on buying also from this company hub wheel motors for my volkswagen beetle 1990 to make it fully electric, without the combustion system and gearbox it will weight around 730kg. Will these motor be good for only city use, but with very bad streets... some streets are off-road. I am really trying to compare between bldc hub motors vs ac 3 phase (gearbox system)
 
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