Leaf / leafmotor / leafbike high efficiency 1500w motor

[Cowardlyduck]

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

Thanks!
I actually did it several years back. At one point I was even playing around with it at 8.4KW and it was going ok till I killed my Adaptto MiniE. After I replaced it I decided to tone it down so I didn't kill the next one.
I also did the same on a Crystalyte HS4080. Worked a treat and both motor's/wheels went together with my Fighter when I sold it earlier this year.

Pushing hubs like this to the limit was fun, but as many others state, it's not using the right tool for the job once you go that far over the rated spec. I would certainly do it again for the right situation, but where the opportunity exists to use a better tool (i.e. beefier hub, or mid drive) then that should be the first option.

As a point of comparison, my LMX64 with it's mid drive has the same pull at 2.5KW that my Leaf did at 7.5KW and doesn't need any cooling mods.

Cheers

 

[markz]

Hub Monster's

Its just a scooter motor, you'd have to find out what it came out of and that info is out there.

 

[ZeroEm]

by markz » Sep 29 2020 1:55am

ZeroEm wrote: ↑Sep 26 2020 9:53pm
Hub Monster's

Its just a scooter motor, you'd have to find out what it came out of and that info is out there.

That is like me doing this

by markz » Sep 29 2020 1:55am

just a scooter motor.

 

[Jasonafriedman]

Hey everyone! This motor looks sick! I want to get one for a 29er full suspension mountain bike. I will be riding it on some pretty good road hills, so I was thinking of asking for a 30mph top speed. Do you think it would run well off a 52v 40-AMP 14Ah battery? I am trying to get 40 miles off a charge.

 

[The Toecutter]

Hey everyone! This motor looks sick! I want to get one for a 29er full suspension mountain bike. I will be riding it on some pretty good road hills, so I was thinking of asking for a 30mph top speed. Do you think it would run well off a 52v 40-AMP 14Ah battery? I am trying to get 40 miles off a charge.

This motor in a 6T wind would suit you well. 40 miles on a charge would probably be unrealistic at a decent speed(20-25 mph) unless you are pedaling with enough force to account for 1/3 of the bike's power requirements, so you'll want a PAS setup, preferably a torque-sensing one. Of course, the cost of a torque sensor and the computer needed to make it work could buy you quite a bit more batteries too...

 

[Jasonafriedman]

Hey everyone! This motor looks sick! I want to get one for a 29er full suspension mountain bike. I will be riding it on some pretty good road hills, so I was thinking of asking for a 30mph top speed. Do you think it would run well off a 52v 40-AMP 14Ah battery? I am trying to get 40 miles off a charge.

This motor in a 6T wind would suit you well. 40 miles on a charge would probably be unrealistic at a decent speed(20-25 mph) unless you are pedaling with enough force to account for 1/3 of the bike's power requirements, so you'll want a PAS setup, preferably a torque-sensing one. Of course, the cost of a torque sensor and the computer needed to make it work could buy you quite a bit more batteries too...

Yeah thanks for the info. Yeah 40 miles is pretty far, but there would definitely be a good amount of human help. I will see if I can get a bigger battery. The other option was to get a BBSHD or a CYC x1 pro, but I think my money would be better spent on getting this motor and spending the extra $ on batteries and a good charger. I have been doing e bike conversions on facebook marketplace, and this customer was hoping for larger range than I typically build. An efficient hub motor would make sense in this use case if I can get enough torque on the large wheel.

 

[Balmorhea]

An efficient hub motor would make sense in this use case if I can get enough torque on the large wheel.

6T 1500W Leaf motor running on 48V 35A in a 29" wheel will slay your hills, unless you're very heavy or they are freakishly steep. That's what I use with an extremely heavy bike GVW, 450ish pounds. It climbs very competently.

That motor-wheel combo has a free speed close to 40 mph, top speed of about 28 without help at the pedals, and about 32 mph with furious pedaling.

If I had it to do over again, I'd probably go for an 8T motor, because I don't really have any use for speed over 25 mph, and I would appreciate better takeoff torque and cruising efficiency.

 

[ZeroEm]

by Balmorhea » Nov 07 2020 3:21am

Jasonafriedman wrote: ↑Nov 06 2020 11:51pm
An efficient hub motor would make sense in this use case if I can get enough torque on the large wheel.

6T 1500W Leaf motor running on 48V 35A in a 29" wheel will slay your hills, unless you're very heavy or they are freakishly steep. That's what I use with an extremely heavy bike GVW, 450ish pounds. It climbs very competently.

That motor-wheel combo has a free speed close to 40 mph, top speed of about 28 without help at the pedals, and about 32 mph with furious pedaling.

If I had it to do over again, I'd probably go for an 8T motor, because I don't really have any use for speed over 25 mph, and I would appreciate better takeoff torque and cruising efficiency.

Careful John will be in here. 8T is a little extream :wink:

 

[john61ct]

go for an 8T motor, because I don't really have any use for speed over 25 mph, and I would appreciate better takeoff torque and cruising efficiency.

Sounds good to me! I assume takeoff torque is related to heavy weight climbing steep hills.

I cannot go smaller than 26" O.D. but using 3+" tires.

I also am not interested in top speeds, at all.

So this motor (highest power version) is commonly available in 8T?

What about it makes it "extreme?"

 

[The Toecutter]

So is this motor (highest power version) commonly available in 8T?

What about it makes it "extreme?"

I wouldn't describe it as "extreme", but an 8T wind will make more torque per amp than a 6T wind, BUT the continuous torque possible from an 8T will be less than either a 6T or 3T wind because the 8T wind has less copper mass than either. The 3T and 6T winds both have the most copper present of all versions, and are therefore capable of the highest continuous torque of all versions, they just differ on how much torque they make per amp(the 3T has roughly twice continuous current rating of the 6T, but the 6T makes roughly twice as much torque per amp compared with the 3T) as well as how many RPMs they spin at per volt(The 3T is twice as fast per volt as the 6T). Of the Leafbike motors available, the 3T and 6T winds will deliver the highest possible peak and continuous power. A performance OR efficiency build would ideally use the 3T wind in a small diameter wheel, but since that isn't what Jasonafriedman was planning on building, an 8T wind would suit him fine if he didn't need to go 30 mph, but based on his description and desire to do 30 mph, a 6T is basically a perfect fit AND has good potential for being used in a higher performance build in the future.

The main advantage of going to a higher T motor wind is the fact that it makes more torque per amp, which allows you to make more torque with inexpensive/low current controllers.

 

[ZeroEm]

Balmorhea lives in Austin. All that stop and go traffic 8T - 36V - 35A controller would be great if you did not want to go over 15 mph. You could just hammer it on take offs and it would get up to top speed with out to many amps. I run an 7T Leafmotor, would like to try a 6T someday. Going to swap out an Edge to try for a while and put my 7T in a 29" wheel but will not be going 24 kph - 32 kph. longest distance will be less than 5 mile trips to the store.

 

[Balmorhea]

3T and 6T winds both have the most copper present of all versions, and are therefore capable of the highest continuous torque of all versions, they just differ on how much torque they make per amp(the 3T has roughly twice continuous current rating of the 6T, but the 6T makes roughly twice as much torque per amp compared with the 3T) as well as how many RPMs they spin at per volt(The 3T is twice as fast per volt as the 6T).

11T has the same copper fill as 3T and 6T. For most applications, that would imply higher than 48 volts. I'm not sure whether 11T tolerates the 35 amps their default controller delivers. I'm sure they'd tell you if you ask, though.

 

[Balmorhea]

go for an 8T motor, because I don't really have any use for speed over 25 mph, and I would appreciate better takeoff torque and cruising efficiency.

Sounds god to me! I assume takeoff torque is related to heavy weight climbing steep hills.

I cannot go smaller than 26" O.D. but using 3+" tires.

I also am not interested in to speeds, at all.

So is this motor (highest power version) commonly available in 8T?

What about it makes it "extreme?"

Starting torque is related to climbing torque, but only to a point. You don't stay at max torque when pulling away from a stop, so gross efficiency isn't important. But if you climb for sustained periods, the fraction of power dissipated as heat becomes very important. So it's more important to match load, speed, and power to keep the motor running in the high efficiency portion of its RPM range.

Leaf will wind whatever turn count you specify. There is enough room in the stator slots for 66 strands of the magnet wire they use. So 3T, 6T, and 11T have full copper fill, 5T and 13T have 65 strands, and 4T and 8T have 64 strands. 7T and 9T have 63 strands. I don't think any of these are bad enough to avoid using the right RPM/volt for your application. I would avoid 10T with only 60 strands.

All my commentary on the matter pertains to the 1500W motor with 35mm magnet width, because that's the only one I have used and researched. There's also a 28mm/1000W version, and a 2000W fatbike version (I'm guessing 45mm?)

 

[John in CR]

That motor-wheel combo has a free speed close to 40 mph, top speed of about 28 without help at the pedals.

Achieving only 70% of no load speed is a sure indication that the motor is grossly too steeply geared. I'll continue to preach until I'm blue in the face that no direct drive hubmotor should be geared with a 29er. While the motor may be able to handle it, that can only be true until you try to climb the wrong hill...or simply the wrong day...and no matter what that choice of wheel size forces you to carry more battery that would a smaller wheel even after the greater performance you get with the motor in a smaller wheel. Instead run the smallest wheel you can live with. Even if it's only down to a 26", it's an improvement, though I regard that as still too big. Plus you get the added benefits of more battery space for the same wheelbase, and with 29ers so much more common for pedal bikes, used 26ers should be far cheaper.

 

[The Toecutter]

11T has the same copper fill as 3T and 6T. For most applications, that would imply higher than 48 volts. I'm not sure whether 11T tolerates the 35 amps their default controller delivers. I'm sure they'd tell you if you ask, though.

I didn't even know they made an 11T! That might pop wheelies...

 

[neptronix]

A magic pie has very close to similar power handling as a leaf motor and has a taller stator and more poles.. for a 29er wheel, it would be my motor of choice over the leafmotor if you had hills to conquer.

The leafmotor is most ideal for wheels between 20 and 26 inches.

John in CR is absolutely right about small wheels and dd hubs :thumb:

I didn't even know they made an 11T! That might pop wheelies...

I was popping wheelies with a 4T on high amps / low volts.. you can make lots of power regardless of what wind you chose

 

[ZeroEm]

My battery is mounted between my front wheels on my trike, no wheelie popping for me 125nm torque stays on the rear wheel.

 

[neptronix]

My battery is mounted between my front wheels on my trike, no wheelie popping for me 125nm torque stays on the rear wheel.

Well yeah.. that's very different than the bike i built to give this motor it's first proper flogging. :lol:
With the 4T on just 47v and 70A of battery current.. it was very hard to keep the front wheel on the ground from a start..

In the video where i am pulling to 59mph on the 4T ( @ 6kW ).. i am nursing the throttle from a stall and also leaning my upper torso on the handlebars to get started. Just too much damn torque.. a nice problem to have, lol.

 

[ZeroEm]

neptronix » Nov 08 2020 3:23pm

I read all your post in this thread and the reason for getting a leafmotor and have been very happy with it. I can get high power and peddle with no power and don't notice any real drag.

 

[Jasonafriedman]

So is this motor (highest power version) commonly available in 8T?

What about it makes it "extreme?"

I wouldn't describe it as "extreme", but an 8T wind will make more torque per amp than a 6T wind, BUT the continuous torque possible from an 8T will be less than either a 6T or 3T wind because the 8T wind has less copper mass than either. The 3T and 6T winds both have the most copper present of all versions, and are therefore capable of the highest continuous torque of all versions, they just differ on how much torque they make per amp(the 3T has roughly twice continuous current rating of the 6T, but the 6T makes roughly twice as much torque per amp compared with the 3T) as well as how many RPMs they spin at per volt(The 3T is twice as fast per volt as the 6T). Of the Leafbike motors available, the 3T and 6T winds will deliver the highest possible peak and continuous power. A performance OR efficiency build would ideally use the 3T wind in a small diameter wheel, but since that isn't what Jasonafriedman was planning on building, an 8T wind would suit him fine if he didn't need to go 30 mph, but based on his description and desire to do 30 mph, a 6T is basically a perfect fit AND has good potential for being used in a higher performance build in the future.

The main advantage of going to a higher T motor wind is the fact that it makes more torque per amp, which allows you to make more torque with inexpensive/low current controllers.

Really interesting stuff! 30mph is not completely necessary, but I assumed that this motor could definitely do both without problems even on a 29er. Having a wind like this should allow for better efficiency at slower speeds, which is perfect for this build. I am excited to do the build, I will post an update on how it goes. I am planning on asking for the kit without spokes or rim so that I can use the existing rim. Maybe it will save on shipping as well!

 

[neptronix]

A given hub motor design does not become much more efficient at low RPM if you change the winding. The difference in efficiency will be in the 1-3% range.. and even that difference in efficiency may be made up for with a different combination of amps / controller mosfets / bus wiring thickness on a higher speed winding.

You can see this here in my simulation where we pit a 5T leafmotor against a theoretical 10T with half the kV. I've lowered the resistance on all components and maxed out the amps so that voltage sag ( which creates the efficiency difference in most winding comparisons ) is not a factor.

Click this link to play with the simulation i designed: https://ebikes.ca/tools/simulator.h...grade=7&grade_b=7&kv_b=5.23&axis=mph&blue=Lbs



The efficiency difference in climbing the hill is 0.7%.. but now we need double the voltage to hit the same speed. So that complicates the choice of your battery.

Really.. consider a higher pole count motor like a magic pie.. or go with a smaller wheel. because the larger the wheel, the slower the rpm/mph, and the lower the continuous power potential the motor will have. A taller motor with a higher pole count will handle a 29" wheel much better.

 

[neptronix]

I read all your post in this thread and the reason for getting a leafmotor and have been very happy with it. I can get high power and peddle with no power and don't notice any real drag.

Wow.. dedicated reader

 

[John in CR]

...30mph is not completely necessary, but I assumed that this motor could definitely do both without problems even on a 29er.

On generally flat terrain sure no problems as long as you don't volt up to try to go too fast, OR you run into the wrong long enough hill, and I can guarantee you that in a 29er that long enough hill wouldn't be all that steep. Which wind you choose won't make a difference in that regard except that those with less copper fill will melt down faster, and slower winds are easier to have controllers that push enough amps to cause the meltdown that you don't realize is happening until it's too late.

Since they don't make a 2t version, the only wind I'd consider buying is a 3t, and with that I could build any low to moderate performance ebike that a customer wanted as long as they didn't want a 29er (which I'd refuse to build and would discourage 26" wheel builds, not because of the wind but because they'll get more range and better performance with a smaller wheel.)

 

[The Toecutter]

Since they don't make a 2t version, the only wind I'd consider buying is a 3t, and with that I could build any low to moderate performance ebike that a customer wanted as long as they didn't want a 29er (which I'd refuse to build and would discourage 26" wheel builds, not because of the wind but because they'll get more range and better performance with a smaller wheel.)

A light-duty 16" DOT moto rim with 13ga spokes laced to a 3T version of the rear-drive freewheel-compatible Leafbike motor with a quality-built 11-34 7-speed freewheel installed, including a Mitas MC2 DOT tire(rated for 62 mph) installed on the rear wheel, would be perfect for this. Unfortunately, that freewheel doesn't exist new anymore. DNP's Epoch and its rebranded variants are crap, but that is about all there is today for a 7-speed freewheel with an 11T small ring present, and even those are under threat of becoming unobtainable. Should be good for 65 mph top speed at 72V with a powerful enough controller to drive it, although 96V would give 87 mph. 150A from the controller to this, a limit of 96V, and a 7 kW power limit would give a heavy tadpole trike set up with this an acceleration rate comparable to the average new car on the road. And the favorable part of this setup's efficiency curve would be very broad.

My cheap 46.8V 10.5AH battery arrived, and now I'm trying to source some small Andersons and XT60s so I can install them to the pack in order to charge it and connect it to the controller. With a 5T wind, setting that battery's draw to 1500W should give me around 35 mph top speed with my Leafbike motor and Phaserunner controller, which without the motor installed or all the heavy things that go with it I can already exceed 35 mph on the flat pedaling it, but the motor WILL at least be able to allow a 30 mph cruising speed, a speed which I can't currently do on the flat for very long. Hopefully the motor's iron loss and hysteresis drag is very low on my 26" bicycle wheel, since there's no point to me in it not being pedal-able with the motor off. When I have my 20S2P 72V 7AH LiIon pack built up, I will then be able to upgrade that top speed to 50 mph with the same amount of power. Then when I do the 20S6P 72V 21AH pack of the same type of cells soon after, I can increase the peak power to 4.5 kW or even slightly more!

I currently have a Schwalbe Marathon Plus Tour tire on my 26" rear wheel. It's about as puncture-resistant as e-bike compatible bicycle tires get, but I wouldn't trust it at 30+ mph. A rear tire blowout on my tadpole trike would be catastrophic at 30+ mph, let alone doing 60-100 mph, so that Mitas MC2 low rolling resistance tire mentioned earlier would provide an acceptable resistance to catastrophic failure from puncture, better than any bicycle tire, and with most of my weight being over the two front wheels, rolling resistance wouldn't be impacted too badly by adding this tire, keeping it pedalable(some testing would be needed to determine if they were of sufficiently low rolling resistance for the front). The Marathon Plus Tour's rolling resistance is not considered to be very good, and I can't say whether the Mitas MC2 would be better or worse regarding this, but the assumption is that it would be close. On the front wheels I could probably get away with 50 km/h continuous-rated Schwalbe Marathon Greenguard e-bike tires, even at higher speeds, since a front blowout would not cause me to lose control as long as the rim is in-tact and the front suspension maintains air pressure, but I would definitely want stronger rims and hubs than the quality bicycle parts I have. These tires are good enough to stop my unmotorized velomobile from 50+ mph, but I've never had to test a panic stop from that speed, for which I'd want to upgrade my Avid BB7 cable-pull brakes to hydraulic brakes(I did have a panic stop from 45 mph and the tires did fine, although the braking wasn't even because the calipers went slightly out of adjustment and getting pulled toward a minivan in the other lane was scary and required careful modulation of the brake lever to avoid going passed the red light and into an intersection with 50 mph cross traffic). With the smaller rear wheel diameter of the 16" moto rim(comparable to a 20" bicycle tire), I'd need a rear suspension installed given the condition of the roads where I am at, and my current body shell would not be able to accommodate for that OR the smaller wheel, so would require a re-design of the shell. But a 3T upgrade and a more powerful controller and sturdier rims all around with a more aero body, a lighter more powerful/energy dense battery, and a roll cage, is something I've been thinking about for the longer term for this KMX, at least in hopes of making it safe to cruise at 45+ mph, while still being pedalable with the motor off.

 

[goatman]

i ran schwalbe marathons on front and they hit too hard at high speeds, switched to 2.35 on the front and it messes with the steering, the front tires get a high speed wobble in the corners, theres too much bounce in them. the 20x2.20 holy rollers i cruise at 60km/h with one hand, i can go no hands at 15/20km/h and they can handle overpass bumps and train tracks at 75km/h pretty much daily. the rear i stuffed a 2.0 tire in a 2.35 tire with 16 moped tube got about 3000km on them with out a flat and changed the torque ramp up rate in the phaserunner to 50ms to help spin the extra mass on take off.