Leaf / leafmotor / leafbike high efficiency 1500w motor

[vladrov]

Hi,

I am in the process of building my first electric bike and need to choose a motor.

Here is a photo of the bike:


It's a 26-inch aluminum frame, 135 mm dropouts.

I will primarily use the bike for commuting to university and work, covering distances of 5-10 km (3-6 miles) one way with a lot of 200 m (656 feet) up and down hills. My average speed will be 30 to 40 km/h (19 - 25 miles/h).

Do you think the 1500W Leaf motor is the right choice?

I am also considering the GMAC and the H212.

The GMAC seems to be more efficient at my required average speed, but it cannot do regenerative braking and may require more maintenance.

The H212's advantage, I believe, is its true 135 mm dropout design, although it has lower efficiency.

Currently, I have a 9-speed cassette on the rear. Would it be possible to buy the cassette version of the Leaf motor and use it without changing the derailleur, the cassette cogs and the shifter if I remove one of the cogs?

I am a bit concerned that this version of the motor might be too wide to fit properly in the frame.

Thank you in advance. I really appreciate your help.

 

[The Toecutter]

I will primarily use the bike for commuting to university and work, covering distances of 5-10 km (3-6 miles) one way with a lot of 200 m (656 feet) up and down hills. My average speed will be 30 to 40 km/h (19 - 25 miles/h).

Do you think the 1500W Leaf motor is the right choice?

What is the rear dropout width? The Leafbike 1500W needs 137mm to fit, and with some leverage, 135mm dropouts can be pulled apart just enough to fit the Leafbike 1500W.

You cannot go wrong with this motor. It's very reliable, well-built, is among the best on the market regarding efficiency, and relatively easy to work on. But which motor among those listed is the best for you really depends upon what your goals are.

The GMAC may see an upgraded version in the near future that allows freewheeling and regen.

 

[vladrov]

What is the rear dropout width? The Leafbike 1500W needs 137mm to fit, and with some leverage, 135mm dropouts can be pulled apart just enough to fit the Leafbike 1500W.

You cannot go wrong with this motor. It's very reliable, well-built, is among the best on the market regarding efficiency, and relatively easy to work on. But which motor among those listed is the best for you really depends upon what your goals are.

The GMAC may see an upgraded version in the near future that allows freewheeling and regen.

135 mm - one of the most important information and I forgot to mention it.

 

[Bullfrog]

Hi,

I am in the process of building my first electric bike and need to choose a motor.

Here is a photo of the bike:
View attachment 355739

It's a 26-inch aluminum frame, 135 mm dropouts.

I will primarily use the bike for commuting to university and work, covering distances of 5-10 km (3-6 miles) one way with a lot of 200 m (656 feet) up and down hills. My average speed will be 30 to 40 km/h (19 - 25 miles/h).

Do you think the 1500W Leaf motor is the right choice?

I am also considering the GMAC and the H212.

The GMAC seems to be more efficient at my required average speed, but it cannot do regenerative braking and may require more maintenance.

The H212's advantage, I believe, is its true 135 mm dropout design, although it has lower efficiency.

Currently, I have a 9-speed cassette on the rear. Would it be possible to buy the cassette version of the Leaf motor and use it without changing the derailleur, the cassette cogs and the shifter if I remove one of the cogs?

I am a bit concerned that this version of the motor might be too wide to fit properly in the frame.

Thank you in advance. I really appreciate your help.

The GMAC CAN do regen...it does not have a freewheel clutch like the MAC:

GMAC - Grin Kits - Product Info

The GMAC motor is Grin’s customization of the powerful rear MAC motor, modified to run without a clutch for regenerative braking, a huge plus for cargo hauling applications. A round axle and integrated torque arm allow for powerful regen without risk of axle spinout.

ebikes.ca

A 10T GMAC laced in a 26" rim would work or a 5T Leaf 1,500w motor would work...those two would be my recommendation.

Use the Grin Tech Motor Simulator to compare the performance of the two motors and that should help you decide which one to go with. Depending on how long and how steep your hills are, the GMAC may run too hot. If you run a 5T Leaf on a 14s/52v battery and put Statorade in it, you will be better off from a "Heat" perspective than with the GMAC.

 

[Bullfrog]

Can anyone tell me if there is a physical difference between the two motors I have listed below? The link to each motor is after the Item ID #.

A. Rear Rotor Winding - 48V 52V 1500W hub motor part, Item ID #LBM481500RN-WRP

Rear Rotor Winding - 48V 52V 1500W hub motor part

Convert your front bike motor wheel to be rear with leaf rear 48v 52v 1500w rotor winding.

www.leafbike.com

and

B. Rear Rotor Winding - 60V 2000W hub motor part Item ID #LBM602000RN-WRP

Rear Rotor Winding - 60V 2000W hub motor part

Convert your front bike motor wheel to be rear with leaf rear 60v 2000w rotor winding.

www.leafbike.com

​

It appears they are identical and the only difference is a slightly faster rpm for the 60v motor as you would expect as you increase the voltage. My bet is Leaf just charges more for a 2000w motor than they do a 1500w motor even though in reality they are identical.

Thanks...I appreciate any info.

 

[Bullfrog]

Can anyone tell me if there is a physical difference between the two motors I have listed below? The link to each motor is after the Item ID #.

A. Rear Rotor Winding - 48V 52V 1500W hub motor part, Item ID #LBM481500RN-WRP

Rear Rotor Winding - 48V 52V 1500W hub motor part

Convert your front bike motor wheel to be rear with leaf rear 48v 52v 1500w rotor winding.

www.leafbike.com

and

B. Rear Rotor Winding - 60V 2000W hub motor part Item ID #LBM602000RN-WRP

Rear Rotor Winding - 60V 2000W hub motor part

Convert your front bike motor wheel to be rear with leaf rear 60v 2000w rotor winding.

www.leafbike.com

​

It appears they are identical and the only difference is a slightly faster rpm for the 60v motor as you would expect as you increase the voltage. My bet is Leaf just charges more for a 2000w motor than they do a 1500w motor even though in reality they are identical.

Thanks...I appreciate any info.

Got an answer from Leaf:
"A and B are the same. But, because works with 60V battery. It's too fast. Sometimes, we will use slower speed winding rotor."

 

[The Toecutter]

Got an answer from Leaf:
"A and B are the same. But, because works with 60V battery. It's too fast. Sometimes, we will use slower speed winding rotor."

Replies in broken Engrish are the best.

 

[Rix]

Hi,

I am in the process of building my first electric bike and need to choose a motor.

Here is a photo of the bike:
View attachment 355739

It's a 26-inch aluminum frame, 135 mm dropouts.

I will primarily use the bike for commuting to university and work, covering distances of 5-10 km (3-6 miles) one way with a lot of 200 m (656 feet) up and down hills. My average speed will be 30 to 40 km/h (19 - 25 miles/h).

Do you think the 1500W Leaf motor is the right choice?

I am also considering the GMAC and the H212.

The GMAC seems to be more efficient at my required average speed, but it cannot do regenerative braking and may require more maintenance.

The H212's advantage, I believe, is its true 135 mm dropout design, although it has lower efficiency.

Currently, I have a 9-speed cassette on the rear. Would it be possible to buy the cassette version of the Leaf motor and use it without changing the derailleur, the cassette cogs and the shifter if I remove one of the cogs?

I am a bit concerned that this version of the motor might be too wide to fit properly in the frame.

Thank you in advance. I really appreciate your help.

""The GMAC seems to be more efficient at my required average speed, but it cannot do regenerative braking and may require more maintenance."" Actually it can, as that is why Justin has that motor specifically designed and built for Grin Cyclery. The "clutch" in the GMAC isn't like the regular MACs, its either "welded up" or the clutch armature is locked up now directly from the supplier. That said, it doesn't free wheel, its will shunt just like a DD hubmotor does when you let off the throttle. What Grin has done is they do have a map available that makes the GMAC "act" like a MAC and freewheel, but they do that with programming. I am not familiar with the whole set up as I haven't actually ran a GMAC yet. I have ran MAC 8, 10, 12, and I have two very customized not available to the public MAC 9T inside of a 12T hub shell.

 

[G8trwood]

Looking at leaf fat snow motors. Are they 35 or 42mm? Looking for slow speed off road torque in a trike. I imagine average speed would be 5?

 

[E-HP]

The MAC 12T mentioned above might work out better for your purposes.

 

[Bullfrog]

Looking at leaf fat snow motors. Are they 35 or 42mm? Looking for slow speed off road torque in a trike. I imagine average speed would be 5?

Depends on which "snow" motor...if it is 135mm or 137mm OLD then the stator is 35mm wide. The snow motor that is 170/190mm wide has the 42mm stator I believe...but don't take my word for it. I am sure about the 135/137 motor's stator but I am going on memory for the 170/190 motor.

 

[Bullfrog]

The MAC 12T mentioned above might work out better for your purposes.

A MAC would not be a good idea at slow speeds, even the 12T MAC will over heat...been there done that.

For 5 mph, the only motor I know of that might work is the wheelbarrow motor from Grin Tech.

 

[G8trwood]

Thanks for replies. Average speed probably 5, but max of 15 would be nice. Smooth slow speed operation is where I run into problems. Quiet is good. Was looking at bafang 62 and then the new grin Fat seems to have better low end torque. I saw the leaf Fat and for the price was wondering if they had sustainable low speed operation.
I have looked at the grin wheelbarrow motor, in video, it sounds about like my chain drive, geared reduction scooter motor to chain drive reduction. I think 40:1 is what I have, so about 4 top speed with 18” tires. Parts were repurposed so not ideal.

 

[E-HP]

Thanks for replies. Average speed probably 5, but max of 15 would be nice. Smooth slow speed operation is where I run into problems. Quiet is good. Was looking at bafang 62 and then the new grin Fat seems to have better low end torque. I saw the leaf Fat and for the price was wondering if they had sustainable low speed operation.
I have looked at the grin wheelbarrow motor, in video, it sounds about like my chain drive, geared reduction scooter motor to chain drive reduction. I think 40:1 is what I have, so about 4 top speed with 18” tires. Parts were repurposed so not ideal.

The leaf motor is not going to work for you, nor will any direct drive hub motor, or most geared hubs. You’d be better off starting a new thread, clearly stating requirements. That way it will be easier for folks to help you rather than having it buried in a 125 page leaf motor thread.

 

[Chalo]

For 5 mph, the only motor I know of that might work is the wheelbarrow motor from Grin Tech.

An 11T or 13T Leaf 1500W or 2000W
motor would probably be pretty good for that, depending on system voltage. In that case I would consult Leaf about how much current the motor can tolerate in that configuration.

Thanks for replies. Average speed probably 5, but max of 15 would be nice. Smooth slow speed operation is where I run into problems. Quiet is good.

Note that when you run a motor at high load at speeds less than 50% of its unloaded maximum speed, efficiency suffers greatly and heat buildup becomes a serious issue. However fast your motor can turn when it's running freely, you don't want to set it up to go continuously a third of that speed at full throttle on a regular basis.

Note also that unless the controller is limiting it first, the motor can make the largest possible amount of power at about 50% of its free speed.

I've been using cheap, dumb "three mode" Chinese controllers lately, and they're blissfully quiet with my direct drive motors.

 

[E-HP]

An 11T or 13T Leaf 1500W or 2000W
motor would probably be pretty good for that, depending on system voltage. In that case I would consult Leaf about how much current the motor can tolerate in that configuration.



Note that when you run a motor at high load at speeds less than 50% of its unloaded maximum speed, efficiency suffers greatly and heat buildup becomes a serious issue. However fast your motor can turn when it's running freely, you don't want to set it up to go continuously a third of that speed at full throttle on a regular basis.

Note also that unless the controller is limiting it first, the motor can make the largest possible amount of power at about 50% of its free speed.

I've been using cheap, dumb "three mode" Chinese controllers lately, and they're blissfully quiet with my direct drive motors.

Average of 5mph to me means above and below 5mph, not 5mph minimum. Below 5 is near stall. It really calls for a mid drive.

 

[Chalo]

Average of 5mph to me means above and below 5mph, not 5mph minimum. Below 5 is near stall. It really calls for a mid drive.

It's all about the system configuration. Here's a simulation I ran using an extrapolated kV for Leaf 13T winding, assuming 24V battery and 24" wheel diameter.

Power is pathetic, but the OP wasn't talking about having 7mph top speed. With the wide stator motor and higher voltage, it could work.

 

[Chalo]

Here's another simulation assuming 11T Leaf 1500W and 36V battery.

 

[E-HP]

It's all about the system configuration. Here's a simulation I ran using an extrapolated kV for Leaf 13T winding, assuming 24V battery and 24" wheel diameter.
View attachment 355932
Power is pathetic, but the OP wasn't talking about having 7mph top speed. With the wide stator motor and higher voltage, it could work.

My assumption is that offroad means that there may be some additional load and possible hills than flat ground. In playing with the simulator in the past, I've found that the RH212 motor to exhibit similar heating as I observe from the Leaf motor under load. Using that as the proxy for the Leaf for modeling heating, and adding a 6% grade to both motors to simulate the load, it looks like heat could present a problem.

Motor Simulator - Tools

Our ebike motor simulator allows you to easily simulate the different performance characteristics of different ebike setups - with a wide selection of hub motors modeled, and the ability to add custom batteries and controllers and set a wide variety of vehicle parameters you'll be able to see...

ebikes.ca

 

[Chalo]

As far as I know, to get a 4 kV winding for any other motor than Leaf, you'd have to wind it yourself. That's what makes Leaf special. You ask for the number of turns you want and they give it to you that way.

I'm sure there are both geared and DD motors that would be inherently better for the job described, but to get them running well at the implied speeds would require DIY custom winding or a very special controller.

 

[G8trwood]

Thank you guys. This discussion is very helpful to me.

Yes off road is higher gradients, but, I’m old and have slowed way down. I wasn’t that familiar with leaf, and their custom windings are what made it appealing. I Had looked at the Mac before, but would like regen if possible and Grin didn’t offer the 12T. Stuck in indecision.


I could always run two drive wheels.

 

[neptronix]

Two geared motors would probably be just the ticket.

The Shengyi SX1/2 can come in regen and non regen variants. The total motor weight will be around 14lbs; these motors are also exceptionally efficient by geared motor standards.

For driving them, a VESC with dual motor capability could provide you with traction control and i think ABS also.

This setup would work pretty nice:



Most people would prefer a mid drive instead, but mid drives come with their own long set of issues vs the simplicity of hub motors.

 

[Bullfrog]

Thank you guys. This discussion is very helpful to me.

Yes off road is higher gradients, but, I’m old and have slowed way down. I wasn’t that familiar with leaf, and their custom windings are what made it appealing. I Had looked at the Mac before, but would like regen if possible and Grin didn’t offer the 12T. Stuck in indecision.


I could always run two drive wheels.

If you are going to ride off road, I would highly recomend a mid drive like the BBSHD.

 

[E-HP]

I Had looked at the Mac before, but would like regen if possible and Grin didn’t offer the 12T.

regen makes no sense at the speeds you’re traveling at.

 

[vladrov]

In the Grin Tech Simulator, the GMAC appears to be much more efficient during acceleration GMAC-Leaf Acceleration, but the Leaf Motor is better while cruising at the same speed (not just top speed) GMAC-Leaf 30km/h Cruising.

Can someone explain why this is the case? Is cruising efficiency more important?

I am considering using a 100/250 VESC and building a 20s3p battery with Samsung INR21700-50S cells. I'm not sure if this is overkill or a good idea. I think it's possible to be done and while I don't need that much power, it would be fun to have it.

In the end, it seems like I need to decide between a fun and overpowered bike, which brings more cost and complexity or a GMAC with a smaller battery and controller that will do the job, make the bike easier to build and much lighter, but won't have that "wow" factor and won't be very special and extraordinary.

Am I right?