QS 3000w midmotor

Electric Motors and Controllers
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PITMIX   1 kW

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Re: QS 3000w midmotor

Post by PITMIX » Oct 03 2020 3:25am

I confirm that the assembly of the pinion with the Woodruff wrench is very strong and no problem. My friend who destroyed his motor shaft had a new shaft supplied by Qs motor.
Aixam 550 Twin retrofit Qs 138 70H, Nuc 24F, LG 20s 60Ah
https://cyclurba.fr/forum/621300/nNlect ... #msg621300
Yamaha TDR 125 retrofit Qs 138 90H, Nuc 24F, LG 20s 60Ah
https://cyclurba.fr/forum/714639/retrof ... #msg714639
Keeway City 50 retrofit Qs 120 70H, Nuc 12F. LG 20s 30Ah
https://cyclurba.fr/forum/698717/e-scoo ... &pageprec=

Jagrkid2186   1 µW

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Re: QS 3000w midmotor

Post by Jagrkid2186 » Oct 27 2020 7:20am

Hey still new to electric motors so any input is appreciated. I have a QS 138 3000w motor, Id like to increase the power to ~5000w. Would doing that be as easy as increasing the amps from the controller or is there more to this than I’m understanding?

Thank you!

j bjork   100 kW

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Re: QS 3000w midmotor

Post by j bjork » Oct 27 2020 7:50am

The spec says 470pA I think. It can probably take more, but about 500A goes a long way. You can probably run 5kw continuous more or less, just make sure that your controller or you have control of the temp. It takes at least 25kw peak without problem.

Jagrkid2186   1 µW

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Re: QS 3000w midmotor

Post by Jagrkid2186 » Oct 27 2020 11:09am

That’s great advice, thank you. By any chance would you happen to know how many amps I’d need to push to the motor to get 5kw out of it? It’s currently at 72v. Once again, I may be asking the wrong question so please feel free to correct my thinking.

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eee291   100 kW

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Re: QS 3000w midmotor

Post by eee291 » Oct 27 2020 11:21am

simple, 5000w/72V=69.44A which is pretty weak IMO.
I'm running it with 450A phase and 250A Battery, I can't even get the motor to get hot with repeated launches and hard acceleration :shock:

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Re: QS 3000w midmotor

Post by Jagrkid2186 » Oct 27 2020 11:30am

Sounds awesome! Thanks for the quick response. Is it really that straightforward or do you need to over estimate amps? Like if I push 100 amps on a 72v current do I really get 7,200w? Or does some of the power get lost to friction?

john61ct   100 GW

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Re: QS 3000w midmotor

Post by john61ct » Oct 27 2020 1:09pm

Current is what it is, at the specific point you measure it.

power watts & amps current get pulled, not pushed.

When voltage is fluctuating all over the place, which it is between the controller and inside the motor, best to stick to Watts power units.

So long as heat is not allowed to destroy the motor, and the other parts can handle delivering Moar!



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eee291   100 kW

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Re: QS 3000w midmotor

Post by eee291 » Oct 27 2020 1:12pm

Well of course you lose power due to friction in the motor and drive train, and not to forget electrical losses inside the motor (eddy currents).
There's also a certain rpm range where the motor runs most efficient, if it's outside that range the motor will convert a ton of energy into heat.

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PITMIX   1 kW

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Re: QS 3000w midmotor

Post by PITMIX » Oct 27 2020 2:29pm

To warm up this engine you really have to ask a lot of it. At 25kW peak on a 400kg vehicle with strong acceleration and high speed for several long minutes, from repeated stops and starts.The engine does not heat up even if it is hot outside.
Aixam 550 Twin retrofit Qs 138 70H, Nuc 24F, LG 20s 60Ah
https://cyclurba.fr/forum/621300/nNlect ... #msg621300
Yamaha TDR 125 retrofit Qs 138 90H, Nuc 24F, LG 20s 60Ah
https://cyclurba.fr/forum/714639/retrof ... #msg714639
Keeway City 50 retrofit Qs 120 70H, Nuc 12F. LG 20s 30Ah
https://cyclurba.fr/forum/698717/e-scoo ... &pageprec=

john61ct   100 GW

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Re: QS 3000w midmotor

Post by john61ct » Oct 27 2020 2:43pm

Which is of course a Very Good Thing!

Let me know if the below makes sense, assuming a powerful FOC controller, say Nucular 24F.

What voltage will give a top speed under 28mph with a 25" outer diameter?

Then which of the windings offered by QS will give best efficiency at ~20-22 mph?

I'm assuming the resulting torque availability will be good for hill climbing with heavy loads, even without gearing?

j bjork   100 kW

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Re: QS 3000w midmotor

Post by j bjork » Oct 28 2020 1:08am

john61ct wrote:
Oct 27 2020 2:43pm
Which is of course a Very Good Thing!

Let me know if the below makes sense, assuming a powerful FOC controller, say Nucular 24F.

What voltage will give a top speed under 28mph with a 25" outer diameter?
It depends on the gearing.
john61ct wrote:
Oct 27 2020 2:43pm
Then which of the windings offered by QS will give best efficiency at ~20-22 mph?
I think there are just one winding. But it doesent really matter, just choose the right gearing.
john61ct wrote:
Oct 27 2020 2:43pm
I'm assuming the resulting torque availability will be good for hill climbing with heavy loads, even without gearing?
What do you mean without gearing? 1:1 gearing? That would be a bad idea in most cases

john61ct   100 GW

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Re: QS 3000w midmotor

Post by john61ct » Oct 28 2020 1:15am

I'm trying to get a handle on Kv/winding vs pack voltage issues

thus eliminating gearing for simplification, even if just a thought experiment.

But also (just curious), isn't there an equivalent DD hub motor version of this unit?

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eee291   100 kW

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Re: QS 3000w midmotor

Post by eee291 » Oct 28 2020 1:48am

john61ct wrote:
Oct 28 2020 1:15am
I'm trying to get a handle on Kv/winding vs pack voltage issues

thus eliminating gearing for simplification, even if just a thought experiment.

But also (just curious), isn't there an equivalent DD hub motor version of this unit?
QS 205 50H for ebikes, for motorcycles they have some up to 14Kw cont.

j bjork   100 kW

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Re: QS 3000w midmotor

Post by j bjork » Oct 28 2020 1:51am

This is a IPM inrunner with a kv about 60
That is 6000rpm at 100v

Hubs are outrunners with kv around 10. (the different kv:s probably starts around 5 and goes up to around 20)
That is 1000rpm at 100v

john61ct   100 GW

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Re: QS 3000w midmotor

Post by john61ct » Oct 28 2020 2:09am

How does this one compare to the Cyclone 3K, for torque grunt at low speeds?

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eee291   100 kW

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Re: QS 3000w midmotor

Post by eee291 » Oct 28 2020 2:53am

john61ct wrote:
Oct 28 2020 2:09am
How does this one compare to the Cyclone 3K, for torque grunt at low speeds?
I'm pretty sure the cyclone uses a planetary gear set inside the casing, but if we compare purely motor shaft torque then the QS always wins, I don't think the cyclone can handle 25kw peaks.

Note that by comparing the cyclone with the qs you may be underestimating the size and weight of the QS 3K.
For a ebkie you might want to go with a smaller mid drive motor like the QS 2K or a Hub.

https://www.alibaba.com/product-detail/ ... 18779.html

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Re: QS 3000w midmotor

Post by john61ct » Oct 28 2020 4:04am

Use case is heavily loaded tandem/cargo slowly climbing long steep mountain "roads".

Just the battery pack might be 100lbs, might need multiple motors.

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eee291   100 kW

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Re: QS 3000w midmotor

Post by eee291 » Oct 28 2020 4:19am

I'm pretty sure the QS 3K is enough to pull a small car, you just need proper gearing that's all.

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PITMIX   1 kW

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Re: QS 3000w midmotor

Post by PITMIX » Oct 28 2020 5:26am

Just watch my videos to understand that this is possible very easily with an 8: 1 reduction gear.
I even tested 9,3: 1.
you can select the subtitles in English
https://youtu.be/FHrRvNgXyIw
Aixam 550 Twin retrofit Qs 138 70H, Nuc 24F, LG 20s 60Ah
https://cyclurba.fr/forum/621300/nNlect ... #msg621300
Yamaha TDR 125 retrofit Qs 138 90H, Nuc 24F, LG 20s 60Ah
https://cyclurba.fr/forum/714639/retrof ... #msg714639
Keeway City 50 retrofit Qs 120 70H, Nuc 12F. LG 20s 30Ah
https://cyclurba.fr/forum/698717/e-scoo ... &pageprec=

SmartStupid   1 µW

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Re: QS 3000w midmotor

Post by SmartStupid » Nov 16 2020 8:19am

Any updates on the new 138 motor with the reduction drive? I have pre ordered this motor and am looking for some clarity. An earlier post in this thread mentioned that this motor comes with a 20mm shaft, to my knowledge this is false. I have both 2D drawings directly from cnqsmotor and a 3D file that they sent me which I have viewed in inventor. The shaft has a 14mm inner diameter and a 17mm outer diameter. This is starting to concern me as the shaft size has decreased from past versions of the motor and will experience more torque due to the reduction drive. Not only that but there are absolutely no sprockets for a 520 chain that are compatible with those shaft dimensions. That being said I have to buy a blank sprocket with a small enough bore to have the tooth pattern custom cut. The only viable sprockets for this operation that I have found are $32.00 a pop :( .

NitramT   1 µW

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Re: QS 3000w midmotor

Post by NitramT » Nov 16 2020 4:17pm

Does anyone have any experience with Kelly or QS motor controllers ? Any specific reason why one or another is better with this specific drive ? Or any other controller that works good for You ?

Bit confused which one should I choose.

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minde28383   10 kW

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Re: QS 3000w midmotor

Post by minde28383 » Nov 20 2020 8:45am

SmartStupid wrote:
Nov 16 2020 8:19am
Any updates on the new 138 motor with the reduction drive? I have pre ordered this motor and am looking for some clarity. An earlier post in this thread mentioned that this motor comes with a 20mm shaft, to my knowledge this is false. I have both 2D drawings directly from cnqsmotor and a 3D file that they sent me which I have viewed in inventor. The shaft has a 14mm inner diameter and a 17mm outer diameter. This is starting to concern me as the shaft size has decreased from past versions of the motor and will experience more torque due to the reduction drive. Not only that but there are absolutely no sprockets for a 520 chain that are compatible with those shaft dimensions. That being said I have to buy a blank sprocket with a small enough bore to have the tooth pattern custom cut. The only viable sprockets for this operation that I have found are $32.00 a pop :( .
Your concern is that 520 standard front sprocket is not readily accessible. I have this and another concern.

Some time ago I saw drawing of this motor and it had 17mm 14mm shaft. I was also interested to find out why not 20mm.
If 17mm/14mm will keep having have issues (brake) I'm sure it will be changed to 20mm.

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minde28383   10 kW

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Re: QS 3000w midmotor

Post by minde28383 » Nov 20 2020 9:05am

NitramT wrote:
Nov 16 2020 4:17pm
Does anyone have any experience with Kelly or QS motor controllers ? Any specific reason why one or another is better with this specific drive ? Or any other controller that works good for You ?

Bit confused which one should I choose.
People are running this motor with various controllers. Votol, Kelly, Nucular. Some good and expensive controllers might be complicated to configure. As long as controller is smart, configurable and supports high rpm motors it can be set. If want cheap get Votol. All three will work with the motor. If looking for specific controller model number - google or look in the forum. Nucular is most advanced of these three. If don't care too much about latest and greatest than get any. People have issues sometimes setting Votol but at the end it works out.
In size and weight, bigger to smaller: Kelly Votol Nucular
In price, bigger to smaller: Nucular Kelly Votol
Other controllers will work but might have some limitations or be not so smooth and / or be not able to reach max rpms if not designed to high rpm motor or be less efficient for such kind motors like this one.

phaseshift   1 mW

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Re: QS 3000w midmotor

Post by phaseshift » Nov 24 2020 11:29pm

Any info on the V4 yet? Considering it or a Motenergy motor for an electric drift kart. Not looking for speed, just torque. 84-96V planned voltage 60AH 10C cells. Anyone running 500A+ ESCs on 96V?

ZERONEST   10 W

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Re: QS 3000w midmotor

Post by ZERONEST » Dec 03 2020 2:18am

PITMIX wrote:
Oct 03 2020 3:25am
I confirm that the assembly of the pinion with the Woodruff wrench is very strong and no problem. My friend who destroyed his motor shaft had a new shaft supplied by Qs motor.
Did your friend fit the shaft himself? And did Qs cover it under the warranty? I had seen a video of someone who had purchased a motor and was supplied with both splined and keyed shafts

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