# Need suggestion for high speed 10/12 inch 3-4kw hub motor

#### biggerpizza

##### 1 mW
I am doing a high speed robot project. Using a 60v 12ah battery pack, unbranded 3kw bldc motor controller and 3kw 10inch hub motor at the moment. The current setting can do 66km/h . Our target is 85km/h.
I thought the controller is a bit dodgy so just ordered a Votol em100sp last week.
Then it turns out the lunyee 3kw hub motor is well over-rated. The actual output is only up to 1.6kw.
Any suggestion for a 10/12inch high speed 3-4kw hub motor?
cheers

How many RPM do you want to reach? Using a 60v 12ah battery pack, unbranded 3kw bldc motor controller.

How high is ... "High speed"? 600RPm? 1200RPM? 2000RPM? Specially wound for like.. even more...? Grin Justin Ebikes built a sailboat with a specially wound high speed hub motor for the propeller... Far greater speed than a typical high speed wound hub motor...

.....we need to know this.

12 RPM is " high speed " for a water wheel.... 120,000 rpm is " high RPM" for a CNC machine spindle motor... 1200RPM... ( on ~72v) is high speed 12" scooter motors.. the power is through the roof if you want... 200w-25kW motors in this size. I got a friend who has a 25kW YUMA that is fast as a rocketbike and reaches 1400RPM... ( lol 70 lb hub motor in a 14" wheel doing 1400RPM goal somewhere around 150kW... under 10 sec bike... )....

Generally hub motors come from 6-18kv. You want a 13-18kV hub motor to turn a 16" dia wheel at 1000RPM... gets you where you want to be.. I think.

(18kV x 60v) = 1060 RPM
(13 x 72v) = 936 RPM... In that general area. kV or 13-18 depending. In those brackets.

Look at the kV number to determine km/h speed at RPm. Need to know the rolling distance ( Dia) of the tire. Like a 1 foot wheel rolls 3.14 feet per rotation.

How many RPM do you want to reach? Using a 60v 12ah battery pack, unbranded 3kw bldc motor controller.

How high is ... "High speed"? 600RPm? 1200RPM? 2000RPM? Specially wound for like.. even more...? Grin Justin Ebikes built a sailboat with a specially wound high speed hub motor for the propeller... Far greater speed than a typical high speed wound hub motor...

.....we need to know this.

12 RPM is " high speed " for a water wheel.... 120,000 rpm is " high RPM" for a CNC machine spindle motor... 1200RPM... ( on ~72v) is high speed 12" scooter motors.. the power is through the roof if you want... 200w-25kW motors in this size. I got a friend who has a 25kW YUMA that is fast as a rocketbike and reaches 1400RPM... ( lol 70 lb hub motor in a 14" wheel doing 1400RPM goal somewhere around 150kW... under 10 sec bike... )....

Generally hub motors come from 6-18kv. You want a 13-18kV hub motor to turn a 16" dia wheel at 1000RPM... gets you where you want to be.. I think.

(18kV x 60v) = 1060 RPM
(13 x 72v) = 936 RPM... In that general area. kV or 13-18 depending. In those brackets.

Look at the kV number to determine km/h speed at RPm. Need to know the rolling distance ( Dia) of the tire. Like a 1 foot wheel rolls 3.14 feet per rotation.
thanks. The one I am using is 10inch scooter hub motor. it's tire diameter is 26cm. So 85km/h is roughly 1740 rpm.

Then it turns out the lunyee 3kw hub motor is well over-rated. The actual output is only up to 1.6kw.
That is nothing new about some sellers lying, just to get more sales.
What is its stator width?

Any suggestion for a 10/12inch high speed 3-4kw hub motor?

Look at QS motors.

There is no budget limit at the moment. But it's better to be a 3-4kw hub motor. Because we just bought votol em100sp. thanks

That is nothing new about some sellers lying, just to get more sales.
What is its stator width?

Look at QS motors.
Thanks I am looking at QS motors at the moment. I have sent message to QS aliexpress shops. But haven't got any reply. And I couldn't find any rpm/torque graph for any QS hub motor like the high speed 10 inch 205 motor online.

Thats why I dont buy anything that others have not bought then shared their experience with this forum.
Notice that word
OTHERS
its plural, not singular.
Then I look for a robust conversation with solid users about their prouduct in the forum.

That means I dont fall for another trick some sellers like to do, which is act like a consumer on a one post from an account that just opened. Or a few posts from a recently opened account.

Another trick they love to do is list false information in the spec sheets or more likely generic info, or dont list critical info.

They list them different wattages for people like you that want high watts, or the normal person that wants 250w like people in the uk want, or 750w here in North America.

Any old motor will do for the scam, like a huge high power motor listed as a lower power motor. Or a low power motor listed as a very high power motor.

There is like a 100 page thread by QS reps here in the forum answering all you ask.

Thats why I dont buy anything that others have not bought then shared their experience with this forum.
Notice that word
OTHERS
its plural, not singular.
Then I look for a robust conversation with solid users about their prouduct in the forum.

That means I dont fall for another trick some sellers like to do, which is act like a consumer on a one post from an account that just opened. Or a few posts from a recently opened account.

Another trick they love to do is list false information in the spec sheets or more likely generic info, or dont list critical info.

They list them different wattages for people like you that want high watts, or the normal person that wants 250w like people in the uk want, or 750w here in North America.

Any old motor will do for the scam, like a huge high power motor listed as a lower power motor. Or a low power motor listed as a very high power motor.
Thanks. That's why I seek for help here. It's a joke the crap motor(Lunyee 60V 10inch rated 3kw) we have now was bought by our boss last year. It's rpm torque table from ebay clearly shows it's output power is only up to 1.5xkw and has only 8N.m torque when rpm is around 16xx. But the QS motor you guys are talking about, has no detail rpm/torque spec listed.

I did found two modules of QS hub motor may meet our requirement listed below.

Again it's better to verify the torque/rpm spec before I put in order.

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There is like a 100 page thread by QS reps here in the forum answering all you ask.

You can see an extensive review of motors from the 35H Leaf which is commonly referred to as "1500w" or the 45h mxus "3kw" to the mxus 5kw (55h???), meaning 35mm stator, 45mm stator, 55mm stator.

Different versions of a motor could mean steel stator or aluminum stator (cooling aspect), curved magnets (no clue, I never found out the benefits if any to curved magnets), two phase sets 3 wires x 2 = 6 sense wires which means your phase wires might not be maximized to their fullest potential (more amps through wire = more power) , but its not really a thing, unless your stuck up on it, like the "Efficiency" people are, hyper-miling it, get every mile out of every watt-hour, like the saving grams on components for the roadies. Some people use stock 12g wire then bump it up to 10awg at axle exit, some stuff bigger wires in or grinding the sharp edge on the axle exit or porting the axle path with a rotary tool. I find its all in the wire you choose, the Teflon PTFE is real stiff plus it has less strands and stiffer strands so its harder to stuff in and around the 90* bend. It was always tuff to stuff in the 3rd 10g ptfe teflon, while the 2nd wire was doable.

Mxus and QS have various versions of the same motor, I am not familiar with QS on each versions, but I know mxus, and the origins of the Edge/Leaf from steel to alum stators.

You see users on the forum take a digital measurement caliper (digital ruler) and measure the stator width, lamination thickness, phase wire diameter. A more advanced user might measure the phase resistance with a MegaOhm meter, or do calculations for various Kv's or Turn Count (3T, 5T, 8T) to optimize their components for their needs.

These are the motors you want to buy, well researched and well studied by independent individuals.
Dont buy just any motor from a random unknown seller because the price is right, unless you want to fiddle around and prepared to be dissappointed, as you were by the sellers lies. Then you might have wait for it to ship to your door if it comes at all, then what about customer service, returns?

Small scooter hubs the tire mounts to the motor, motorbike/bike hubs are laced with spokes.

Power to size would be a concern?
Go wider!
Double stator hubs are out there. You should good to find a 3-4kw scooter hub for your robot project on the QS website.

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I don't know if any of the ones in this search apply, but there are a number of dyno charts for various QSmotors out there; this search finds a few of them

thanks guy. Got confirm from QS sails on Aliexpress this afternoon. The 3.5kw 10inch hub motor rapid version will do.

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