Leaf / leafmotor / leafbike high efficiency 1500w motor

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Hickbeard   100 W

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Re: Leaf / leafmotor / leafbike high efficiency 1500w motor

Post by Hickbeard » Aug 11 2020 8:48am

Thanks bud. Says video is unavailable but I've found another one that goes through them all.

Can do cruise with the down button apparently. That sounds good. Definitely giving that a go.

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Djhandz   100 mW

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Re: Leaf / leafmotor / leafbike high efficiency 1500w motor

Post by Djhandz » Aug 16 2020 10:29am

I picked up one of these motors locally but with no controller
Please could you knowledgeable guys recommended me a controller for best performance and silent running

Thanks in advance

Balmorhea   100 kW

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Re: Leaf / leafmotor / leafbike high efficiency 1500w motor

Post by Balmorhea » Aug 16 2020 1:57pm

Djhandz wrote:
Aug 16 2020 10:29am
I picked up one of these motors locally but with no controller
Please could you knowledgeable guys recommended me a controller for best performance and silent running
For silence, you need a sine wave controller. The Leaf 1500W motor is pretty noisy with a trapezoidal wave controller.

Do you have a battery already? If so, the battery has limitations you need to respect in choosing a controller.

If you want a true 1500W maximum output, get a 35A controller. You can get a higher rated controller for more powerful climbing and acceleration, or a lower rated controller to match the requirements of a battery that isn’t rated for that much current.

A Grin 40A controller would be a good match to a Leaf motor.
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Re: Leaf / leafmotor / leafbike high efficiency 1500w motor

Post by Djhandz » Aug 16 2020 2:40pm

Thanks Balmorhea I already have a few 6s lipo 10ah packs that I have been running for a while with no problems pulling peaks of 60 amp but mainly peaks of 30amp and avaraging around 10 amps out of them on my commute
Yes them controllers look alright but there out of stock
Any idea on how often they stock them or any other recommendations

I would like to be able to pull peaks of 3000watt just short burst to get up hills

Balmorhea   100 kW

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Re: Leaf / leafmotor / leafbike high efficiency 1500w motor

Post by Balmorhea » Aug 16 2020 3:09pm

Djhandz wrote:
Aug 16 2020 2:40pm
I would like to be able to pull peaks of 3000watt just short burst to get up hills
My experience looking for controllers suggests that cost goes up fast, and choices dwindle sharply, when you go higher than 40A. Assuming 48V, you’ll need about 60A from the controller to deliver 3kW electrical, and close to 80A if you want 3kW at the wheel.
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Re: Leaf / leafmotor / leafbike high efficiency 1500w motor

Post by Djhandz » Aug 16 2020 3:25pm

thanks mate. i might just bite the bullet and get a phaserunner and run at 60v. i like how compact they are..

would this be a good combo?

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Re: Leaf / leafmotor / leafbike high efficiency 1500w motor

Post by Balmorhea » Aug 16 2020 3:35pm

Djhandz wrote:
Aug 16 2020 3:25pm
thanks mate. i might just bite the bullet and get a phaserunner and run at 60v. i like how compact they are..

would this be a good combo?
I don’t have any direct experience with Phaserunner. I do know that some folks here have observed that they get noticeably less power from it than from other controllers of equal or lower nominal rating. Whether that can be fixed by programming, I don’t know.

60V only makes sense if you have a relatively slow wind version of the motor. If it’s the default winding, higher voltage will just move the motor’s most efficient speed range up to a road speed that you won’t have enough power to attain.
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Re: Leaf / leafmotor / leafbike high efficiency 1500w motor

Post by Djhandz » Aug 16 2020 3:44pm

thanks for the useful info dude not sure of the winding but assuming its default would you recommend i stick to 12s lipo 50,4v fully charged?

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Re: Leaf / leafmotor / leafbike high efficiency 1500w motor

Post by Balmorhea » Aug 16 2020 4:16pm

Djhandz wrote:
Aug 16 2020 3:44pm
thanks for the useful info dude not sure of the winding but assuming its default would you recommend i stick to 12s lipo 50,4v fully charged?
I think it's worth trying. If you use a 26" wheel, that's probably a top speed of 35ish miles per hour. It's realistic for the amount of power you'll have available. Certainly your cruise speed, whatever it is, will be more efficient than it would be with higher voltage.
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Djhandz   100 mW

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Re: Leaf / leafmotor / leafbike high efficiency 1500w motor

Post by Djhandz » Aug 16 2020 4:35pm

Thankyou very much that's what I will do as i want efficiency too

Many thanks for your help

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Re: Leaf / leafmotor / leafbike high efficiency 1500w motor

Post by John in CR » Aug 17 2020 11:53am

Balmorhea wrote:
Aug 16 2020 4:16pm
Djhandz wrote:
Aug 16 2020 3:44pm
thanks for the useful info dude not sure of the winding but assuming its default would you recommend i stick to 12s lipo 50,4v fully charged?
If it’s the default winding, higher voltage will just move the motor’s most efficient speed range up to a road speed that you won’t have enough power to attain.

Certainly your cruise speed, whatever it is, will be more efficient than it would be with higher voltage.
Please stop making up these kinds of ridiculous statements. Winding and voltage for a given motor are useful for determining top speed. That's it. The whole idea of a motor's "most efficient speed range" is ridiculous, because the peak efficiency point varies with throttle position. For a given motor, iron core losses are fixed at a given rpm regardless of voltage or winding. Copper losses are the same for a given torque regardless of pack voltage or winding (assuming the same amount of copper).

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Re: Leaf / leafmotor / leafbike high efficiency 1500w motor

Post by Balmorhea » Aug 17 2020 2:52pm

John in CR wrote:
Aug 17 2020 11:53am
Balmorhea wrote:
Aug 16 2020 4:16pm
Djhandz wrote:
Aug 16 2020 3:44pm
thanks for the useful info dude not sure of the winding but assuming its default would you recommend i stick to 12s lipo 50,4v fully charged?
If it’s the default winding, higher voltage will just move the motor’s most efficient speed range up to a road speed that you won’t have enough power to attain.

Certainly your cruise speed, whatever it is, will be more efficient than it would be with higher voltage.
Please stop making up these kinds of ridiculous statements. Winding and voltage for a given motor are useful for determining top speed. That's it. The whole idea of a motor's "most efficient speed range" is ridiculous, because the peak efficiency point varies with throttle position. For a given motor, iron core losses are fixed at a given rpm regardless of voltage or winding. Copper losses are the same for a given torque regardless of pack voltage or winding (assuming the same amount of copper).
There’s nothing ridiculous or untrue about matching rpm/volt, voltage, and power required, in such a way as to get the bike close to 75-80% of its unloaded speed. What do you find so hard to understand about that? The default winding of a Leaf 1500W motor doesn’t have sufficient power to get to 75-80% of its unloaded speed if you feed it 60V (unless you stuff in enough amps to burn it). It makes no difference how much you want to reach that speed; there just isn't enough power to do it. So you run 100% of the time in a lower efficiency range. Turning down the voltage reduces the power required to get to 80% of the free speed, and the system runs more efficiently because it’s closer to the peak efficiency rpm.

Maybe it could also work if you fitted it with a tiny donut tire. But that would be ridiculous.
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Re: Leaf / leafmotor / leafbike high efficiency 1500w motor

Post by John in CR » Aug 17 2020 10:02pm

Balmorhea wrote:
Aug 17 2020 2:52pm
John in CR wrote:
Aug 17 2020 11:53am
Balmorhea wrote:
Aug 16 2020 4:16pm
Djhandz wrote:
Aug 16 2020 3:44pm
thanks for the useful info dude not sure of the winding but assuming its default would you recommend i stick to 12s lipo 50,4v fully charged?
If it’s the default winding, higher voltage will just move the motor’s most efficient speed range up to a road speed that you won’t have enough power to attain.

Certainly your cruise speed, whatever it is, will be more efficient than it would be with higher voltage.
Please stop making up these kinds of ridiculous statements. Winding and voltage for a given motor are useful for determining top speed. That's it. The whole idea of a motor's "most efficient speed range" is ridiculous, because the peak efficiency point varies with throttle position. For a given motor, iron core losses are fixed at a given rpm regardless of voltage or winding. Copper losses are the same for a given torque regardless of pack voltage or winding (assuming the same amount of copper).
There’s nothing ridiculous or untrue about matching rpm/volt, voltage, and power required, in such a way as to get the bike close to 75-80% of its unloaded speed. What do you find so hard to understand about that? The default winding of a Leaf 1500W motor doesn’t have sufficient power to get to 75-80% of its unloaded speed if you feed it 60V (unless you stuff in enough amps to burn it). It makes no difference how much you want to reach that speed; there just isn't enough power to do it. So you run 100% of the time in a lower efficiency range. Turning down the voltage reduces the power required to get to 80% of the free speed, and the system runs more efficiently because it’s closer to the peak efficiency rpm.

Maybe it could also work if you fitted it with a tiny donut tire. But that would be ridiculous.
As usual you try to mix in true statements to support your nonsensical ones that you continue to state with authority. The problem is that you don't really understand how our motors operate. Yes getting the voltage and winding combination right is important for a given top speed target, though I disagree with a 75-80% of no-load speed as a target, since on flat ground with no wind my bikes all achieve close to 90% of no-load speed. Where you miss the boat is WRT efficiency, because the way our controller/motor combinations work, at a given speed and load the motor will operate at the same efficiency whether the pack is 48V, 60V or 72V. You'll just be running at lower throttle position at higher voltage to achieve the same speed as is possible at 48V.

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Re: Leaf / leafmotor / leafbike high efficiency 1500w motor

Post by Balmorhea » Aug 17 2020 11:27pm

John in CR wrote:
Aug 17 2020 10:02pm
Yes getting the voltage and winding combination right is important for a given top speed target, though I disagree with a 75-80% of no-load speed as a target, since on flat ground with no wind my bikes all achieve close to 90% of no-load speed. Where you miss the boat is WRT efficiency, because the way our controller/motor combinations work, at a given speed and load the motor will operate at the same efficiency whether the pack is 48V, 60V or 72V. You'll just be running at lower throttle position at higher voltage to achieve the same speed as is possible at 48V.
Your method works fine, if you’re using lots of kW to do a single kW’s job. But if you are running a 1500W motor at 1500W, throttling back on a motor that has too fast a winding only means lower speed, without any of the extra torque you gave up when you used a too-fast winding.

Yes, that means I am assuming you’re using a 48V 35A controller rather than a 12V 150A controller, because that’s what real people actually do.
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Re: Leaf / leafmotor / leafbike high efficiency 1500w motor

Post by John in CR » Aug 18 2020 1:09am

Balmorhea wrote:
Aug 17 2020 11:27pm
John in CR wrote:
Aug 17 2020 10:02pm
Yes getting the voltage and winding combination right is important for a given top speed target, though I disagree with a 75-80% of no-load speed as a target, since on flat ground with no wind my bikes all achieve close to 90% of no-load speed. Where you miss the boat is WRT efficiency, because the way our controller/motor combinations work, at a given speed and load the motor will operate at the same efficiency whether the pack is 48V, 60V or 72V. You'll just be running at lower throttle position at higher voltage to achieve the same speed as is possible at 48V.
Your method works fine, if you’re using lots of kW to do a single kW’s job. But if you are running a 1500W motor at 1500W, throttling back on a motor that has too fast a winding only means lower speed, without any of the extra torque you gave up when you used a too-fast winding.

Yes, that means I am assuming you’re using a 48V 35A controller rather than a 12V 150A controller, because that’s what real people actually do.
The max power I run has absolutely nothing to do with it. Once again you miss the point and spew nonsense, which when I run across it will be pointed out. You said that running a high pack voltage could result in running at lower efficiency 100% of the time, and that is 100% incorrect. You bring up the notion of an "more efficient rpm range". You made that statement, because you don't understand how our motors work and how our controllers vary and control their speed, but in actuality there's a new efficiency graph for every throttle position and relatively low rpm can have quite high efficiency.

As far as the motor is concerned it "sees" the same thing to run at 20mph whether the battery pack is at 24V or 48V or 60V or 200V, which means the motor will run at essentially the same efficiency. That is of course assuming the same type of controllers are used. Sine wave controllers will slightly more efficient than square wave types that approximate the sinus shape using square blocks of pulses, and some of the newer Field Oriented Controllers can be a significant step up in efficiency at any rpm, but again pack voltage won't matter except to the controller which can run very slightly less efficiently at the lower % throttle due to a high pack voltage.

If efficiency is a primary concern, then in addition to the type of controller used, another big factor (especially if hill climbing is involved) is wheel size, and yes with hubmotors the smaller the diameter of wheel you can live with the better in terms of performance and efficiency. If the roads you use are good enough, then wheel diameter doesn't make a difference. That's why millions are perfectly content with their 20" folders.

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Re: Leaf / leafmotor / leafbike high efficiency 1500w motor

Post by John in CR » Aug 18 2020 1:31am

Balmorhea wrote:
Aug 16 2020 3:35pm
60V only makes sense if you have a relatively slow wind version of the motor. If it’s the default winding, higher voltage will just move the motor’s most efficient speed range up to a road speed that you won’t have enough power to attain.
Last but not least, though it's virtually never discussed on the forum, is the perfectly valid strategy of using a fast wind motor combined with high voltage, but limiting top speed through current limiting, so you end up with a top speed that's only 50-60% of no-load speed. While peak efficiency is 2 or 3 points lower this way, you gain it back in efficiency during acceleration so overall efficiency ends up the same or better, because it really broadens and flattens the efficiency curve. The result is a very smoothly accelerating bike with mild manners. Because current limits are set low, the system is virtually indestructible with the only way to burn up the motor is to get on a long hill too steep for it to climb and bogging it down to a stall.

The beauty of that kind of approach, especially if you can live with a smaller tire like a 20" or 24", is that you end up with a motor that can handle far greater performance at common voltages than a slow wind model, so it can grow with you as your performance demands increase.

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Re: Leaf / leafmotor / leafbike high efficiency 1500w motor

Post by Balmorhea » Aug 18 2020 4:11am

You are ignoring the fact that when you use a motor with higher rpm/volt, you get lower torque/amp. Nothing you do with cutting throttle, limiting current etc. will buy back the torque you sacrifice that way. And if that torque isn’t enough to get you to the motor’s peak efficiency speed, then you wont get peak efficiency. Depending on how overfast your winding is (again, assuming normal voltages and respecting the motor’s power rating) you may not be able to get up to that speed at all, at any efficiency.
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Re: Leaf / leafmotor / leafbike high efficiency 1500w motor

Post by John in CR » Aug 18 2020 11:38pm

Balmorhea wrote:
Aug 18 2020 4:11am
You are ignoring the fact that when you use a motor with higher rpm/volt, you get lower torque/amp. Nothing you do with cutting throttle, limiting current etc. will buy back the torque you sacrifice that way. And if that torque isn’t enough to get you to the motor’s peak efficiency speed, then you wont get peak efficiency. Depending on how overfast your winding is (again, assuming normal voltages and respecting the motor’s power rating) you may not be able to get up to that speed at all, at any efficiency.
No, I'm not ignoring anything and I even discussed what you mentioned taken to the extreme in my last post. You on the other hand are ignoring the simple fact that slow and fast wind configs of a given motor are the same motor capable of exactly the same performance in all respects (speed, torque, efficiency, etc), however, slow wind motors are generally more limiting and better performance is easier with more room to grow in the future with a faster wind motor. When someone is shopping for a 1500W motor instead of a 500W motor, then they're obviously interested in performance. Peak efficiency is just a number useful in comparing different motors to each other, and really only comes into play as a significant factor for those who cruise for long periods at constant speed.

Also, just because my most used bikes now have 15kw, 21kw, and 31kw of peak input power and extreme speeds doesn't mean I don't have plenty of experience running bikes with 500W-2kw of power. The first 5 motors I got from China were 1200W motors with 60V20A controllers in 2008, which I used for years. 4 of those motors are still in service running bikes with 2kw up to as high as 10kw.

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Re: Leaf / leafmotor / leafbike high efficiency 1500w motor

Post by Djhandz » Aug 19 2020 3:51am

Interesting discussion guys I will try both 12s and 18s lipo and see how it goes

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Re: Leaf / leafmotor / leafbike high efficiency 1500w motor

Post by john61ct » Aug 19 2020 5:15am

It would be "even better" for the community if disagreements could just focus on lying out "the Truth" as you understand it, without personal attacks, unnecessarily slagging off at fellow members who have contributed so much of value.

That said, between the two of you, my case is:

big hills, heavy loads

cannot go too small a wheel because gravel / dirt roads and rough tracks

care nothing for "fun" nor top speed, pure utility transport, even 15-20mph would be fine

range / energy efficiency is only a medium priority

most important is torque, especially standing starts in stop-and-go city commuting, but also

when the load is extra heavy, and/or that long steep hill is not allowing much speed.

Yes, the limiting factor is shedding heat, yes gearing would be nice set those aside for now.

Question: slow wind or fast wind, makes any difference?

Assume I can choose the controller and pack voltage to suit


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Re: Leaf / leafmotor / leafbike high efficiency 1500w motor

Post by 2old » Aug 19 2020 12:31pm

Good questions John 61, and probably I'll be excoriated for this, but seems like mid-drive would be best for your application. Should you want to use a hub for some reason, once you decide on the voltage (unless you have the option to choose anything), so let's say 52V, select a "slow wind" which AFAICT develops it's maximum torque at a lower rpm than "fast", and make sure your battery has enough amps to supply the requirement of the controller you choose. Maybe won't have optimum efficiency, but maybe will never know (or care). I'm not a fan of tires smaller than 26" because (for me) the ride is inferior especially on dirt. My primary forays into hubs were with a front hub, 350w, 36V, 15 amp, 10 ah battery, 20 mph, and rear hub 1000w, YESCOM, 52V, 30 amp, 10 ah battery, 35 mph and both work perfectly as commuters (for me), but I didn't use for cargo.

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Re: Leaf / leafmotor / leafbike high efficiency 1500w motor

Post by john61ct » Aug 19 2020 12:34pm

The question was in service of my better understanding the theoretical math issues.

I do realize there are other approaches to a practical solution

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Re: Leaf / leafmotor / leafbike high efficiency 1500w motor

Post by 2old » Aug 19 2020 3:17pm

Sorry I'd like that too, something more practical than esoteric nuances. I realize that you knew all that I said.

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Re: Leaf / leafmotor / leafbike high efficiency 1500w motor

Post by Balmorhea » Aug 19 2020 4:04pm

john61ct wrote:
Aug 19 2020 5:15am
That said, between the two of you, my case is:

big hills, heavy loads

cannot go too small a wheel because gravel / dirt roads and rough tracks

care nothing for "fun" nor top speed, pure utility transport, even 15-20mph would be fine

range / energy efficiency is only a medium priority

most important is torque, especially standing starts in stop-and-go city commuting, but also

when the load is extra heavy, and/or that long steep hill is not allowing much speed.

Yes, the limiting factor is shedding heat, yes gearing would be nice set those aside for now.

Question: slow wind or fast wind, makes any difference?

Assume I can choose the controller and pack voltage to suit
So your requirement is high torque (for climbing) and pretty good efficiency (for mitigating heat) at relatively low speed.

What you want is a motor with lots of poles, wide magnets, and a large diameter. These things maximize torque capability. But since your question is about windings, let’s assume you are specifically talking about the Leaf 1500W motor.

John is correct when he says that any winding of that motor is capable of the same maximum torque. A fast wind does it at low voltage and high current, and a slow winding does it with higher voltage and lower current. The maximum torque is determined by physical characteristics of the motor: diameter, magnet strength, copper fill, etc. No matter the winding, it will always make the same torque for the same heat, as long as copper fill is equal.

As e-bikers, we have practical limitations as to what voltage and current levels are widely available and economical, and what wire gauges are feasible to work with. These represent blanks in the equation we can fill in right away. Nobody wants to spend thousands on a kiloamp controller, or have to use #0000 gauge cable, if they can use cheap and readily available components instead. So the right, or at least most practical, way to approach it is to decide on a power level (in this case 1500W rated) and a voltage (the motor manufacturer assumes 48V, so I do too because it’s easy to work with).

Immediately, these choices allow us to fill in more blanks. Knowing the power and voltage means you’ll be using a 35A or 40A controller, and your battery must be able to support a current of that size.

You specified a not-too-small wheel, so let’s say 26”. The default winding of the Leaf 1500W motor has published performance data for it. Here’s the table. So you see its unloaded speed at 48V is 600 rpm, and when loaded at full throttle, it makes 1500W at a little over 500 rpm and a little under 30 Nm of torque. 510 rpm on a 26 inch wheel is 39.5 mph. So you can see the rated power and speed won’t match even on a flat smooth road, let alone a steep hill.

I know (because I asked the folks at Leaf) that the unloaded speed of an 8 turn Leaf motor is 290 rpm at 48V. So... same motor, same efficiency, same battery, same controller. That means at the same power and voltage, you get more than twice as much torque. It will make its rated 1500W power at 60 Nm of torque and about 240 rpm, which is 18.6 mph for a 26” wheel.

Now these numbers aren’t exactly representative of what you might measure on a dyno, because the copper fill can vary by a small amount between different turn counts. But they’re not going to be wrong by much more than the difference in fill percentage.

You could in fact get functionally equivalent performance from the default winding by using 24 volts and 80 amps. But that’s a more exotic and costly controller, and a 6 gauge wire harness instead of 12 gauge. Remember the wires going into the motor are the same size in either case, so they’ll heat up 4 times as much at double the current. It’s not nearly as big a deal to raise the voltage and lower the current on a slow wind motor, to make it run at a higher speed.

In the case you’ve laid out, and assuming the Leaf 1500W motor because that’s our topic, I would decide what’s the lowest top speed that I could accept, and ask Leaf to make me a motor for that speed. I’d get a 48V controller from them too, because it’s sure to work and it plugs right in. And that way, I’d be assured of the most torque that my battery, controller, and operating parameters allowed. What I would not do is order the default hub and then figure out how to feed it less voltage and more current than it was designed for.
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Re: Leaf / leafmotor / leafbike high efficiency 1500w motor

Post by john61ct » Aug 20 2020 12:44pm

OK, thanks I'll work on digesting that.

Please confirm some basics from my past notes:

The T number, as in 8T vs 10T, stands for turns

more turns means higher winding, aka slower winding

more turns means less speed per volt, aka lower Kv, and also more torque per amp

thus fewer turns means greater speed per volt, less torque per amp.

The efficiency, aka heat generated for a given torque remains the same, unaffected by winding

Changing the winding **only** changes the ratio of volts to amps for a given wattage, quantity of power

This example not wrt Leaf specifically:

Whether "10T at 48v & 20A" or "8T at 36v & 30A", about the same performance, efficiency, torque, speed etc

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