Leaf / leafmotor / leafbike high efficiency 1500w motor

[Djhandz]

Thanks for that John that's what I thought. I am glad you chimed in as I was going to initially pm you my question as I know you know your stuff..

I ran the 22s today did around 30 mile and it was nice to have the extra capacity had fun with burst of 4.5kw. (my cycle analyst limits to 4.5kw)
Had no issues at all temps at the top of the longest climb home about 1 mile long motor was only 29c

Enjoying this leafmotor so far

 

[John in CR]

Lower throttle settings are also less efficient, as your graph shows.

No, no, NO. You're looking at different conditions to the left of cruising speed where torque and power are significantly higher, so they occur for less time. The difference in efficiency at speed of 87.2% and 87.1% is small enough to be ignored, and is nothing compared to the efficiency loss of going the same speed with a bigger wheel. For the same cruising speed with the same motor and controller and batteries to get the same speed achieves just 84% efficiency in a 26" wheel and 81.8% efficiency in a 29er, and that's at steady state cruise with a cool motor. That kind of efficiency difference piles up to a hotter and less efficient motor as the copper heats up. Obviously the place to look for efficiency gains that matter for a given speed is a smaller wheel, and the beauty of going that route is that you can have your cake and eat it too by having better performance in all respects with greater efficiency and reduced overall consumption.

Not to mention folks are unlikely to change their throttle habits when adding a few percent more volts. They'll just ride a little harder.

First, it's not a few % increase in voltage. It's a 22% increase going from 18s to 22s, and that's going to result in a quite noticeable increase in performance that costs very little in terms of consumption rate getting up to a given cruising speed. Better performance, greater overall safety, and still get more range, what more can you ask for? Plus for those longer rides you can still ride more conservatively and get the full extra range benefit of the added batteries. I'd argue that once you get your ebike to a performance level that satisfies you and the novelty wears off, then it becomes even easier to ride in a manner that extends range when needed (more judicious use of the throttle, more coasting to use less braking, and even add lower speeds). Despite the performance potential of my bikes increasing to the extreme of what is possible, my average wh/mile has gone down significantly, and that's despite more opportunities to show up cars motorcycles leaving stoplights, the greater rolling resistance of using motorcycle tires, and lugging around larger heavier battery packs.

 

[Balmorhea]

Lower throttle settings are also less efficient, as your graph shows.

No, no, NO. You're looking at different conditions to the left of cruising speed where torque and power are significantly higher, so they occur for less time.

They occur all the time if you use a real adult bike with full diameter wheels.

The real efficiency to be had is to set up a bike to go the speed you want to go, and not faster than that. Then for any amount of power, you get maximum time spent at equilibrium speed, regardless your habits with the throttle.

One of the worst things about cars is that they're made to go much faster than it's ever appropriate to drive them. You've just translated that kind of pathological thinking to the light EV world (making yours less light in the process).

 

[John in CR]

Lower throttle settings are also less efficient, as your graph shows.

No, no, NO. You're looking at different conditions to the left of cruising speed where torque and power are significantly higher, so they occur for less time.

They occur all the time if you use a real adult bike with full diameter wheels.

The real efficiency to be had is to set up a bike to go the speed you want to go, and not faster than that. Then for any amount of power, you get maximum time spent at equilibrium speed, regardless your habits with the throttle.

One of the worst things about cars is that they're made to go much faster than it's ever appropriate to drive them. You've just translated that kind of pathological thinking to the light EV world (making yours less light in the process).

You must walk around with a concrete helmet on all the time, since factual info has no chance of sinking in. While it's fine for you to believe whatever incorrect info you choose, it's inappropriate to spread on a forum where people are here to learn and share. Leave it to someone in Texas to try to belittle anything with smaller diameter wheels than they believe is appropriate. To make matters worse now you insinuate that the only appropriate throttle position is WOT to achieve "real efficiency". The only thing pathological going on is your inability to admit when you're wrong. That wouldn't be a problem except that the overwhelming majority of the statements you make about electric bikes are incorrect.

This notion of a one speed ebike is just icing on the cake, especially in a thread about a 1500W rated hubmotor. Conditions should determine the appropriate speed to ride.

Let's also get this prejudice against any wheels smaller than 26" out of the way, because it really doesn't belong in any discussion of direct drive hubmotors. Did you know that the world speed record for a bicycle ridden in a conventional riding position belongs to a bike with 20" wheels? The differences in rolling resistance are so tiny that it's laughable to even bring up. The only thing big wheels have going for them is that they offer a smoother ride over poor surfaces, but suspension can take care of that.

On the other side of the coin, smaller wheels means more space to fit batteries. They also make your bike more nimble and maneuverable. Smaller wheels make any DD hubmotor better able to climb hills. They are more efficient in all conditions, and they give you better performance regardless of the size and weight of the hubmotor. That also means if weight is of significant importance that you can use a smaller lighter motor than would be required with a larger wheel. These advantages are not small differences either. The performance differences are ones you can feel, whether it's hill climbing or acceleration, and the efficiency advantage is one you can readily see with a cooler motor and increased range.

 

[Balmorhea]

Did you know that the world speed record for a bicycle ridden in a conventional riding position belongs to a bike with 20" wheels? The differences in rolling resistance are so tiny that it's laughable to even bring up. The only thing big wheels have going for them is that they offer a smoother ride over poor surfaces, but suspension can take care of that.

That record was set on a groomed salt pan. If that were the surface we all rode on, wheel diameter wouldn't matter so much. And the power for that kind of event comes from a race car motor. For comparison, hour records (set without motor pacing but also on a smooth surface) have all been set on bikes that used full sized wheels. That's because all the power comes from a limited supply of muscle power.

I can remember an hour record bike that used a larger than normal rear wheel.



It's true that suspension can take away some of the sting of donut wheels. With a more-is-more vehicle like a 6000 pound SUV, it's consistent with the design philosophy. But with a bicycle, it's counter to the whole principle. I mean, you could get a smoother ride by making it an air cushion vehicle too, or making it fly-- but like suspension, that would come with a set of tradeoffs.

I'm not talking about a one-speed e-bike, either. I'm talking about a bike that tops out at the speed it's appropriate to cruise at. It's easy, it's pleasant, it's efficient, and it helps maintain peace and safety on the road. And it maximizes the bike's capabilities at all speeds less than cruise.

 

[The Toecutter]

A friend of mine ordered the front drive version of the 1500W motor for the 3-wheled car we've been building. At the time, I was not aware that it came with smaller phase wires than the rear drive variant of the motor.

What are the largest phase wires that will fit? My guess is 12 awg, but I want to be sure.

We plan to add at minimum fans into the case of this motor as well as ferrofluid and possibly add liquid cooling, but the small phase wires it came with are the current bottleneck in peak power. We'd like to get 10 kW peak or more. This is going to be a 200-300 lb car with a 250 lb driver, running a 120V Kelly controller.

As for the motor for my electric velomobile, I'm just going to stick with ferrofluid and the larger phase wires it already comes with, maybe do 7 kW peak with the Phaserunner controller, if I build up a pack that can deliver it. Planning on no less than 4 kW peak.

 

[ZeroEm]

The rear leafmotor had an axle change years back. I don't know but what's in my head is they used the 2000w leafmotor axle and cut it down. Don't remember if I read that or just think it. Others have commented on it back in this thread. Luke had a thread on running larger phase wires thru an axle.

The front is rated at 1500w with the 2mm wires. They upgraded the rear for the hot rodders that run alot more thru. Last time I talked about phase wires had my wires crossed and amberwolf had to correct me.

Remember the front is a 100mm wide motor not as wide as the rear.

Did not get to test the front leafmotor before I gave it to my brother, wished that it was kept.

 

[Cowardlyduck]

I managed to cram 12awg silicone wire through my Leaf axle after stripping off the insulation and replacing it with heat shrink.

Also did the cooling fans, FF, heatsinks etc. That's how I managed to push it past 7.5KW.
Unfortunately a lot of the images got lost, but here's a few I dug up:


All the details were in this thread:
https://endless-sphere.com/forums/viewtopic.php?f=30&t=56965&start=475

Cheers

 

[John in CR]

The way to get maximum copper through the axle is with magnet wire. Group the strands into the 3 phases at the ends, but pass the bundle through the axle as one circular round bundle of wire including the hall temp sensor wires which can also be thinner gauge magnet wire. I've done it several times and start with a single layer wrap of stretched electrical tape to get the bundle tight and aligned. Then 2 layers of heat shrink. On a little 9C axle I got the equivalent of between 10 and 11awg through the axle for each phase wire.

 

[Mikebike]

My A2B metro has been down for quite some time. Bad battery (built a new one), Bad controller (ordered and waiting for my new nucular controller to come in) and now also Bad hall in the rear hub motor. On sugesstion of another ES member my plan is to update with the new leaf kit listed below.

https://www.leafbike.com/products/diy-bike-conversion-kit/20-inch-48v-52v-1500w-rear-bike-motor-kit-1185.html

I have a 150mm rear dropout, a 20 inch rear wheel with a 3 inch wide tire, rear disk brake, and 7 speed cassette. I would like to have everything go back as it was with the new leaf motor/wheel combo but I am concerned things will not line up properly (disk brake, cassette, etc.)
I am 220 pounds and I ride mostly dirt/gravel roads and trails with small rolling hills around my property in Virginia.
Trying to understand what speed/wind motor I should order based on my weight and riding style. 30mph is plenty of speed for me and would prefer good pulling power from 0 to 30 over top end speed over 30.
Is there anything else you all can think of that I should watch out for when ordering this kit?

 

[ZeroEm]

Get a 4T motor.

 

[The Toecutter]

My A2B metro has been down for quite some time. Bad battery (built a new one), Bad controller (ordered and waiting for my new nucular controller to come in) and now also Bad hall in the rear hub motor. On sugesstion of another ES member my plan is to update with the new leaf kit listed below.

https://www.leafbike.com/products/diy-bike-conversion-kit/20-inch-48v-52v-1500w-rear-bike-motor-kit-1185.html

I have a 150mm rear dropout, a 20 inch rear wheel with a 3 inch wide tire, rear disk brake, and 7 speed cassette. I would like to have everything go back as it was with the new leaf motor/wheel combo but I am concerned things will not line up properly (disk brake, cassette, etc.)
I am 220 pounds and I ride mostly dirt/gravel roads and trails with small rolling hills around my property in Virginia.
Trying to understand what speed/wind motor I should order based on my weight and riding style. 30mph is plenty of speed for me and would prefer good pulling power from 0 to 30 over top end speed over 30.
Is there anything else you all can think of that I should watch out for when ordering this kit?

What battery pack voltage do you plan to run? If you're running a 48V pack and get a 4T, and you'll just barely top out at 30 mph. If you have 72V pack, a 6T wind at 72V will get you roughly the same top speed as a 4T wind at 48V, but the 6T wind will make more peak torque per amp of controller current. You could also decide you want more top speed and just go with a 4T wind at 72V and do around 45 mph top end.

 

[Mikebike]

Don't see running anything more than 48volts so 4t it is.
Thanks for the help!

 

[ZeroEm]

Then later you add more volts if more speed is needed.

 

[markz]

:thumb: Neat trick!
At which point out of the axle do you solder on wire to the phase wires?
Is your controller really close by the motors axle?

The way to get maximum copper through the axle is with magnet wire. Group the strands into the 3 phases at the ends, but pass the bundle through the axle as one circular round bundle of wire including the hall temp sensor wires which can also be thinner gauge magnet wire. I've done it several times and start with a single layer wrap of stretched electrical tape to get the bundle tight and aligned. Then 2 layers of heat shrink. On a little 9C axle I got the equivalent of between 10 and 11awg through the axle for each phase wire.

 

[John in CR]

:thumb: Neat trick!
At which point out of the axle do you solder on wire to the phase wires?
Is your controller really close by the motors axle?

The way to get maximum copper through the axle is with magnet wire. Group the strands into the 3 phases at the ends, but pass the bundle through the axle as one circular round bundle of wire including the hall temp sensor wires which can also be thinner gauge magnet wire. I've done it several times and start with a single layer wrap of stretched electrical tape to get the bundle tight and aligned. Then 2 layers of heat shrink. On a little 9C axle I got the equivalent of between 10 and 11awg through the axle for each phase wire.

If you're planning to take the magnet wire all the way to the controller, I would separate the phase wires into separately insulated bundles and slip heat shrink over each hall wire and then the hall bundle before the run gets to a place were it needs to flex for suspension movement. I wouldn't want to rely on only the magnet wire varnish to insulate the phases from each other in any section that sees movement. If it was on a bike where the motor wheel need frequent removal, I'd only go to less than a foot from the axle, just enough for the drip loop. Then I'd terminate the phases with bullet connectors at staggered lengths for easy removal and no way to mix up which goes to which.

 

[neptronix]

I managed to cram 12awg silicone wire through my Leaf axle after stripping off the insulation and replacing it with heat shrink.

Also did the cooling fans, FF, heatsinks etc. That's how I managed to push it past 7.5KW.
Unfortunately a lot of the images got lost, but here's a few I dug up:
DSC_2764 (Small).jpg
DSC_2763 (Small).jpg
All the details were in this thread:
https://endless-sphere.com/forums/viewtopic.php?f=30&t=56965&start=475

Cheers

That's a beautiful sight, my dude
I never took mine past 6kw due to the simple fact that i couldn't keep the front wheel on the ground.
Rad to hear that someone has finally taken it to max

 

[The Toecutter]

My friend used a pneumatic grinder inside the axle to just barely fit a bundle of wire-taped and duct-tape wrapped 12 AWG along with the bundle of auxillary wires through the front mount version of the 5T 1500W motor. It was an ordeal. A 72V 200A Kelly controller will be driving it, albeit it's probably not going to be run more than 150A. Earlier I said 120V Kelly controller, but was mistaken as to the model he had. Eventually, we will probably run a higher voltage controller.

I'm just going to run mine with ferrofluid to start with, once I get a usable battery pack put together. I already have the "black lightening" version, so my phase wires should be good for 96A peaks(limited by a Phaserunner controller) and 30-40A continuous. It'll be interesting to see how cool or hot to the touch the motor is after a few bursts of 7 kW accelerations interrupted by 1500-2000W held steady at max speed...

 

[Balmorhea]

How much do you think motor efficiency can possibly be improved from 90%?

Hint: not "much more".

There have been prototype hub motors that have approached 98% efficiency such as the AMZ motor I mentioned earlier, but they've never reached the market.

It's as if you haven't given much thought to why that is. It must be because everybody in the industry is lazier and less insightful than yourself.

It's possible to make a jet airplane that launches and lands vertically. Why doesn't everybody have one?

 

[The Toecutter]

It's as if you haven't given much thought to why that is. It must be because everybody in the industry is lazier and less insightful than yourself.

Projection, a bit much? I can think of lots of reasons why they may not be on the market, but I'm not employed by them and don't know the inside story as to what was discussed about it.

I'm just stating what is possible. This isn't even close to rocket science.

 

[ZeroEm]

Astro Flight motors

All these factors allow the 32XX motors to achieve a peak efficiency as high as 94%. Furthermore, the motors maintain their high efficiency over a wide range of voltage and current values. This makes the 32XX flexible in customers' systems.

 

[The Toecutter]

Too bad Astroflight doesn't make a hub motor that can make that sort of efficiency at lower RPMs. These mid drive units need a reduction ratio to run at an rpm appropriate for moving an e-bike or trike. For their size and weight, they can pack a massive amount of peak power with the right controller driving them.

And as far as the direct drive hub motors available on the market for ebikes and trikes, the Leafbike is about as good as it gets, efficiency wise. There's so much low hanging fruit to improve which wouldn't cost a whole lot of money on a per unit basis...

I've always wondered what a smallish 7-10 lb direct drive hub motor with 0.1 mm laminations, a 25-30mm stator width, and a 6-phase or 9-phase design similar to a hubmonster could do with today's tech... Maybe one day I'll get the chance to design and build one. If I ever get a CNC mill, that will be on my list of things to do. Given what has already been done, 95% peak efficiency and 88-92+% broad operating efficiency can be had with the correct design, and that would open doors to all kinds of vehicle design possibilities.

 

[ZeroEm]

They have the Astroflight 4535 15kw 94% efficiency, make a good mid drive but it is out of stock.

 

[The Toecutter]

They have the Astroflight 4535 15kw 94% efficiency, make a good mid drive but it is out of stock.

The $2,500 price tag and the description seem to point to it being hand made. At 12 lbs, 15 kW peaks are extraordinary. It can probably handle a bit more than that for short periods of time.

That said, the Hub Monster that used to be sold by John in CR for $600 looks like a great bargain by comparison!

My conjecture is that the Leafbike 1500W is relatively cheap mainly because of its production volume. On a per peak kW basis, it's still more expensive than the Hub Monster.

 

[ZeroEm]

Yes, agreed. There are good motors out there but people don't want to pay so we are stuck with the leafmotor for now. But I would not want all the noise. John in CR quit selling his Hub Monster's. Maybe one of you should start a factory and make a few thousand.