Leaf / leafmotor / leafbike high efficiency 1500w motor

[Bullfrog]

I don't know why you guys even bother. Here's a full suspension production ebike for under $2000, WIRED Freedom , that peaks at 3200w, 1500w continuous. It comes with a total of 35ah in (2) 60v batteries.
A guy who bought one said on EBR that it can do 40 mph, him thinking more or less continuously.
What could possibly be wrong with this deal of an ebike?

Problems you are going to run into with the bike you referenced...not a chance in Hell it will do 1500w continuously without over heating. Check the Grin Tech web site for the GMAC and it will give you an idea the maximum wattage you can run through a good geared hub motor continuously: GMAC - Grin Kits - Product Info Just FYI it is about 1,000 watts.

Same issue once you go over about 28-30 mph...the amperage will be too high to do it for very long without over heating. Max power for 5 minutes is around 2,600 watts.

Having the battery on the rear rack is going to make the bike handle like crap. Having the other battery on the downtube will help but not enough to make the bike handle good.

For the price, it appears to be a decent deal but there are things that jump out at me that are cheap like the rear suspension...no linkage to change the rising rate...usually found on higher quality bikes. Can't tell what fork it has or how big the brakes are but those are two areas where most try to save money and they shouldn't.

Thanks for bringing it up but most of us enjoy the build process and my bike with a 1500w motor cost me about $1,200 total.

 

[E-HP]

I don't know why you guys even bother. Here's a full suspension production ebike for under $2000, WIRED Freedom , that peaks at 3200w, 1500w continuous. It comes with a total of 35ah in (2) 60v batteries.
A guy who bought one said on EBR that it can do 40 mph, him thinking more or less continuously.
What could possibly be wrong with this deal of an ebike?

Watching the YouTube videos it takes forever to get to 40, even pedaling downhill. It’s a tank.

 

[G8trwood]

Received a reply from Leaf on motor windings for slower speed. Peter was recommending a 7.33 Kv but can also do a 5 or 6 Kv. The Grin all axle Fat slow is a 7Kv as comparison.
Running far to many simulations, it looks like at lower speeds (old people trike) I lose speed with the 5Kv but gain range at low to mid throttle of up to 30%. From the torque graphs, I can see why they recommend the 7.3 and why Grin has the Fat Slow at 7Kv. Very flat torque vs the 5Kv being higher but falling off quickly. I have been running based on upright fat bike and the max weight in the drop down.
Is there simple math for figuring out needed torque at startup?

 

[neptronix]

That bike's speed is pretty impressive. I still don't want it at $1000 for a list of reasons that continues to grow the more i look at it and the more we talk about it.

Received a reply from Leaf on motor windings for slower speed. Peter was recommending a 7.33 Kv but can also do a 5 or 6 Kv. The Grin all axle Fat slow is a 7Kv as comparison.
Running far to many simulations, it looks like at lower speeds (old people trike) I lose speed with the 5Kv but gain range at low to mid throttle of up to 30%. From the torque graphs, I can see why they recommend the 7.3 and why Grin has the Fat Slow at 7Kv. Very flat torque vs the 5Kv being higher but falling off quickly. I have been running based on upright fat bike and the max weight in the drop down.

Let's keep it simple. What top speed do you want?

>Is there simple math for figuring out needed torque at startup?

The 5T model of leafbike is on the ebikes.ca simulator.

5T is a pretty reasonable winding & most prebuilt batteries can push enough amps to make for a fun experience.
40A is the minimum you want for the 4T to get it moving quick, 30-35A the minimum for a 5T.

 

[vladrov]

How much torque is too much, for example, when the front wheel no longer stays on the ground?

 

[neptronix]

How much torque is too much, for example, when the front wheel no longer stays on the ground?

That's my definition; i know that i shouldn't get into an argument with physics because i will lose

 

[vladrov]

I mean how much torque is needed to lift the front wheel in a normal riding position. I calculated 277 Nm for me and my bike, but if I'm not mistaken, there was talk of 120-140 Nm here.

 

[Rix]

I mean how much torque is needed to lift the front wheel in a normal riding position. I calculated 277 Nm for me and my bike, but if I'm not mistaken, there was talk of 120-140 Nm here.

This much torque.

 

[G8trwood]

Wheelie bars are already on some wheelchairs, so……..

 

[neptronix]

I had extreme difficulty keeping the front wheel on the ground when starting at 6kW ( 85A X 72v ) on a 4T, despite having a very long wheelbase, leaning on the handlebars, and just barely nudging the throttle.

Ah but those were the days before we had FOC controllers, so i was really rawdogging the pure output of the motor.

You will probably be happy with the leaf unless you're looking to go highway speeds!

 

[ebike4healthandfitness]

Leaf bike 1500w reported with broken side cover:

Popping and grinding coming from rear wheel

A few months ago I started hearing a popping and grinding sound coming from around my rear wheel. This was only when I put a decent amount of pressure on the pedals. The sounds got louder and louder over time. I originally thought it was the bottom bracket. I took it to a bike shop and they...

endless-sphere.com

Popping and grinding coming from rear wheel

A few months ago I started hearing a popping and grinding sound coming from around my rear wheel. This was only when I put a decent amount of pressure on the pedals. The sounds got louder and louder over time. I originally thought it was the bottom bracket. I took it to a bike shop and they...

endless-sphere.com

Did this version have aluminum threads for the side cover? Or is this an instance of a steel threaded side cover breaking?

Neptronix, does your motor from 2015 have aluminum or steel threads?

 

[neptronix]

I sold that bike with it's motor 8 years ago, sorry.
Known weakness in many hubs, but this is the first report i've seen on the leaf in a decade. I'd imagine it's a very rare failure.

I've sheared the freewheel interface off an early version MAC once. I don't stand on the pedals but i do have monster legs.

You won't be pedaling a lot on an almost 2kw rated motor...

 

[E-HP]

I mean how much torque is needed to lift the front wheel in a normal riding position. I calculated 277 Nm for me and my bike, but if I'm not mistaken, there was talk of 120-140 Nm here.

I think around 100nm on a bicycle framed, non fat ebike. I get a small lift with my chest/stomach resting on the front bars (at ~160nm) without throttle ramping. From a normal riding position, and my throttle ramp set to 1.3V/sec (so 3 seconds to hit full throttle), it will try to flip over if I use more than 1/2-3/4 throttle from a stop or accidentally apply pedal pressure. With no ramping, it will lift the front at 15mph if I hit the throttle to hard, or at 20mph if I switch to speed 2 or 3 while on the throttle and that's something like 100nm. Hence, I believe 100nm.

5T, 7kW

 

[vladrov]

You will probably be happy with the leaf unless you're looking to go highway speeds!

No, I’m only using that as a reference point to make sense of how the torque produced by the motor actually feels.

In my calculations, I didn’t consider that the pivot point is between the tire and the ground and not on the axle. This is why I incorrectly calculated 277 Nm.

 

[neptronix]

The amount of amperage that will throw you off the bike varies based on your weight, frame geometry, wheelsize, etc etc.

Just buy a programmable controller and run a few rounds of tune & test and you can get a very precise answer. We can only offer you educated guesses here.

 

[vladrov]

New motors may actually be more powerful because it has less end turn losses sapping power on every rotation. Possibly there is the same or very close to the same effective amount of copper. I would imagine they're a tad lighter, too.

Too bad they don't have an updated dyno sheet. By moving to super flat windings with much less end turn losses, i would bet they are more efficient.

I think you’re right.

There are two independent factors that could cause the lower kV in the later motor versions:

• A smaller amount of copper, which leads to higher resistance and lower current for the same voltage. This was my first thought.
• Better interaction between the windings and the core due to cleaner winding techniques. In this case, the back EMF rises faster with the RPMs, causing the motor's top speed to drop

From visual observation, I also believe the second factor is more significant.

 

[vladrov]

The amount of amperage that will throw you off the bike varies based on your weight, frame geometry, wheelsize, etc etc.

Just buy a programmable controller and run a few rounds of tune & test and you can get a very precise answer. We can only offer you educated guesses here.

Yes, yes, I know. It was just a rough approximation to get an idea when I played with the simulator. Your answers were more than helpful and sufficient for my needs. Thanks.

 

[neptronix]

Yeah, anything that affects back-EMF ( changing stator lamination thickness, pole count, width, amount of useless copper on the ends, etc ) will cause that kV to change.

 

[E-HP]

No, I’m only using that as a reference point to make sense of how the torque produced by the motor actually feels.

In my calculations, I didn’t consider that the pivot point is between the tire and the ground and not on the axle. This is why I incorrectly calculated 277 Nm.

Might be better to describe the feel you want, then build the system to achieve it. The steeply descending torque curve of electric motors can make a bike feel uncontrolable off the line, but still leaves a lot to be desired in the mid range, where the most fun is. So, the unusable low speed torque needs to be controlled in order to have impressive torque in the midrange. You may need to build a bike that goes faster than you want to go, with totally uncontrolable torque off the line, in order to have the torque where you want it, so things like throttle ramping are necessary to lower the torque at speeds where it’s not desireable. I want gobs of torque between 25 and 35 for times that I need to ride near cars. I don’t need to go fast, so I don’t, but I needed the higher voltage to raise the torque curve in the midrange. I don’t need all of that torque off the line, so I control/limit it with a slow ramp. Sometimes to get what you want, you need to deal with the unwanted consequences, but you’ll have a grin on your face when you get it dialed in.

 

[ebike4healthandfitness]

Problems you are going to run into with the bike you referenced...not a chance in Hell it will do 1500w continuously without over heating. Check the Grin Tech web site for the GMAC and it will give you an idea the maximum wattage you can run through a good geared hub motor continuously: GMAC - Grin Kits - Product Info Just FYI it is about 1,000 watts.

Same issue once you go over about 28-30 mph...the amperage will be too high to do it for very long without over heating. Max power for 5 minutes is around 2,600 watts.

Having the battery on the rear rack is going to make the bike handle like crap. Having the other battery on the downtube will help but not enough to make the bike handle good.

For the price, it appears to be a decent deal but there are things that jump out at me that are cheap like the rear suspension...no linkage to change the rising rate...usually found on higher quality bikes. Can't tell what fork it has or how big the brakes are but those are two areas where most try to save money and they shouldn't.

Thanks for bringing it up but most of us enjoy the build process and my bike with a 1500w motor cost me about $1,200 total.

Here is the motor the Wired Freedom bike is based on:

S-Type R1200 (Cassete）

www.hentach.com

However, Wired did say (in the picture below) that motor was fully customized for them. Perhaps they went with .27mm laminations to boost the efficiency and thus continous power?



P.S. Looking back on the old .35mm lamination MAC motor and it is only listed as >80% efficient (scroll down to "Overview" in the link below):

Mac135mm Axle 0.35mm Laminations E-bike Motor - Buy E-bike Motor,E-bike Motor,E-bike Motor Product on Alibaba.com

Mac135mm Axle 0.35mm Laminations E-bike Motor - Buy E-bike Motor,E-bike Motor,E-bike Motor Product on Alibaba.com

www.alibaba.com

 

[E-HP]

Here is the motor the Wired Freedom bike is based on:

S-Type R1200 (Cassete）

www.hentach.com

However, Wired did say (in the picture below) that motor was fully customized for them. Perhaps they went with .27mm laminations to boost the efficiency and thus continous power?

View attachment 358304

P.S. Looking back on the old .35mm lamination MAC motor and it is only listed as >80% efficient (scroll down to "Overview" in the link below):

Mac135mm Axle 0.35mm Laminations E-bike Motor - Buy E-bike Motor,E-bike Motor,E-bike Motor Product on Alibaba.com

Mac135mm Axle 0.35mm Laminations E-bike Motor - Buy E-bike Motor,E-bike Motor,E-bike Motor Product on Alibaba.com

www.alibaba.com

The hybrid gears aren't too noisy and the weight isn't bad. Does it have an integrated toque arm like the Grin motors?

But the bike is over 100 lbs and the fat tires don't help. Needs a diet.

 

[gromike]

Those "hybrid" spur gears in that motor can't be good in the long run.

 

[Bullfrog]

Here is the motor the Wired Freedom bike is based on:

S-Type R1200 (Cassete）

www.hentach.com

However, Wired did say (in the picture below) that motor was fully customized for them. Perhaps they went with .27mm laminations to boost the efficiency and thus continous power?

View attachment 358304

P.S. Looking back on the old .35mm lamination MAC motor and it is only listed as >80% efficient (scroll down to "Overview" in the link below):

Mac135mm Axle 0.35mm Laminations E-bike Motor - Buy E-bike Motor,E-bike Motor,E-bike Motor Product on Alibaba.com

Mac135mm Axle 0.35mm Laminations E-bike Motor - Buy E-bike Motor,E-bike Motor,E-bike Motor Product on Alibaba.com

www.alibaba.com

If you go to the Hengtai web site: Products you'll see the above motor is rated for 1,000w. I can believe 1,000w but it will over heat if you run it at 1,500w continuously. It will take a little while but eventually it will over heat.

The MAC has pretty high efficiency...I did a run with the Grin Tech Motor Simulator and you'll see it is close to the same as the Leaf 1,500w motor. Actually the MAC has a higher efficiency than the Leaf in this run but they are so close they almost lay on top of each other: Motor Simulator - Tools

The Hengtai motor may handle 1500w continuously if you lace it in a rim that is small enough i.e. a 20" rim and get a winding that has a top speed lower than about 30 mph. The wheel diameter determines the final gearing so a smaller wheel is geared lower than a larger diameter wheel.

 

[ebike4healthandfitness]

If you go to the Hengtai web site: Products you'll see the above motor is rated for 1,000w. I can believe 1,000w but it will over heat if you run it at 1,500w continuously. It will take a little while but eventually it will over heat.

The MAC has pretty high efficiency...I did a run with the Grin Tech Motor Simulator and you'll see it is close to the same as the Leaf 1,500w motor. Actually the MAC has a higher efficiency than the Leaf in this run but they are so close they almost lay on top of each other: Motor Simulator - Tools

The Hengtai motor may handle 1500w continuously if you lace it in a rim that is small enough i.e. a 20" rim and get a winding that has a top speed lower than about 30 mph. The wheel diameter determines the final gearing so a smaller wheel is geared lower than a larger diameter wheel.

The 1000w rating must be a copy and paste error because the motor is listed in two places, "1000w" and "above 1200w". Also notice the "1000w version" and the "above 1200w version" have different product model numbers:

S-Type R1000

www.hentach.com

S-Type R1200 (Cassete）

www.hentach.com

Also don't forget this motor is a a good bit wider and heavier than the MAC as it weighs 5.5 kg and uses fat bike rear spacing not 135mm.

 

[neptronix]

..so anyway can we talk about the leafbike on the leafbike thread instead?