Leaf / leafmotor / leafbike high efficiency 1500w motor

..so anyway can we talk about the leafbike on the leafbike thread instead? :)
How about those Leaf 1500w motors :).

IMO what you are seeing is all the relatively inexperienced people think they can find a better deal or a motor that can handle more power...and you CAN. BUT you can't find a better deal on a motor that can handle more power :). The newbies want to come here and show us what they found and they are all excited because they think they found a better deal on a motor that can handle more power...BUT it doesn't exist.

The Leaf 1500w motor isn't magic, it is just a fairly well built motor with a 35mm stator that runs pretty efficiently for a competitive price. There are smaller/lighter motors that would be better in some applications and larger/heavier motors that would work better for some applications but across the board, the Leaf 1,500w Direct Drive motor is tough to beat.
 
I am still having trouble deciding between getting the Leaf motor or a Bafang M635 torque sensing BBSHD.

Can anyone share top speeds at 48v or 52v with the 4t? Some people shared previously but I think that was for use at 72v.
Are there any other suggestions for a controller capable of maybe 2.5kw to 3.5kw bursts?

Thanks,

The thing holding me back from the BBSHD is wear on drive train for regular use at higher speeds around 50-60km/h, and the relatively lower top speed (I gather around 55km/h). Also regen for the braking on the Leaf is good, more for the lack of break pad wear rather than the modest energy regained
 
The thing holding me back from the BBSHD is wear on drive train for regular use at higher speeds around 50-60km/h, and the relatively lower top speed (I gather around 55km/h). Also regen for the braking on the Leaf is good, more for the lack of break pad wear rather than the modest energy regained
4T = 13.1175kV

Put in your weight or change anything else per your assumptions (custom controller, battery, etc.). Have fun!
 
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I played around with that but it is only the 5t. I think there is another motor roughly equivalent to the 4th maybe the Crystalyte 35 from Memory, but the simulator has only the 5t listed

Edit: re. Suggestions for controllers, I meant what people actually use for that level of performance. There are a lot of different controllers on the simulator

And now I see E-HP has linked to a way to figure out the 4t in the simulator, thanks
 
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Can anyone share top speeds at 48v or 52v with the 4t?
Here's a rough data point for you:

4T Leaf 35H in the rear, pretty upright fatbike frame, 100-406 tires front and rear, 14S battery, at ~50V battery voltage under a load of ~2500W, with 20A of flux weakening, I'm able to sustain about 62km/h on level ground. HTH.
 
I played around with that but it is only the 5t. I think there is another motor roughly equivalent to the 4th maybe the Crystalyte 35 from Memory, but the simulator has only the 5t listed

Edit: re. Suggestions for controllers, I meant what people actually use for that level of performance. There are a lot of different controllers on the simulator
Show advanced > Set custom kV

For 4T - around 12.1, according to Leaf.
 

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Thanks. Going from 58km/h to 68km/h goes from 1600w to 2600w, an extra 1000w for 10km/h gain. Hardly worth it usually.
Just bend over more when you want to go faster, and for the same watts. Pump up your tires for your speed runs for an extra 1/2kmh.

 
I pretty much always rode my leaf in a tucked / down low position on the lowest rolling resistance 2.2" tires i could buy.
The higher the RPM, the lower the air load, the better.
 
I am still having trouble deciding between getting the Leaf motor or a Bafang M635 torque sensing BBSHD.

Can anyone share top speeds at 48v or 52v with the 4t? Some people shared previously but I think that was for use at 72v.
Are there any other suggestions for a controller capable of maybe 2.5kw to 3.5kw bursts?

Thanks,

The thing holding me back from the BBSHD is wear on drive train for regular use at higher speeds around 50-60km/h, and the relatively lower top speed (I gather around 55km/h). Also regen for the braking on the Leaf is good, more for the lack of break pad wear rather than the modest energy regained
I'll help you make your decision real easy. Do you ride off road any, if yes go with the BBBSHD. Leaf is a great motor but the weight distribution, handling, motor over heating, ability to change the driving gear ratios...all better with the BBSHD.

If you want to ride on pavement and/or good dirt roads then the Leaf or a MAC/GMAC would be my choice. Just depends on how fast you want to cruise. Above ~28 mph then go with the Leaf. If you don't want to go faster than 28 mph then go with the 10T MAC/GMAC. The difference is the MAC/GMAC will over heat if you push enough amperage through it to go faster than about 28-30 mph. There is some good info on the Grin Tech web site. The Leaf will have lower acceleration per amp but it is much more tolerant of higher amperage without over heating and Statorade will also help a lot in the Leaf.

If you go with the MAC/GMAC or the Leaf then the wheel you have the motor laced in determines your final gearing and I'd recommend you NOT go with anything larger than a 26" wheel and a 24" wheel would be better.

Use the Grin Tech Motor Simulator to compare motors and check your temperatures...it is a very useful tool, use it. You can change the Kv values to get more info on the Leaf and you can use the Crystalyte 35xx series of motors to get a good estimate on the temperatures your Leaf will see.

The top speeds that the Grin Tech Motor Simulator gives you are very accurate if you plug in good data.

Kv values for the Leaf are:

4T / 13.1 Kv
5T /10.1 Kv
6T / 7.0 Kv

I got them here and this is a good article on the Leaf motor as well: Leafbike 1500W hubmotor, the mid-sized hot rod.

Any time you see an article written by "Spinningmagnets" it is worth reading. He is a pretty sharp guy and does his research before publishing information.
 
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What is the closest motor/s in specs to the Leafbike for a cheaper price? Price plus shipping is a bit high for the Leaf for me. Does anyone know if any MXUS, Suringmax, etc motors come close to the specs or performance of the Leaf?

This for example looks pretty good SR35HD-1500W_Suringmax
 
AFAIK you won't find a motor this well built and efficient at this cost, anything at a lower price point ( sometimes even higher ) is going to lack there.

I'm a big fan of the RH212 if you don't need all the power the leaf has, but, i'm thinking if you're in Australia, you may not like the shipping costs.

RH212 Fast Wind
 
QS212 1200W might be available cheaper than Leaf (mine was), but the 135mm rear version won't support a multi speed freewheel. Also it isn't available in the variety of turn counts that Leaf is, which is half the battle for real world efficiency.
 
AFAIK you won't find a motor this well built and efficient at this cost, anything at a lower price point ( sometimes even higher ) is going to lack there.

This motor could be so much better. The fact that it is among the best offerings on the hub motor market is a travesty, considering how much technology has advanced on this front. We should/could have a ~95% efficient PMDC hubmotor available to us now. Imagine the peak power that could be made in a smaller/lighter/more narrow motor that allows even 9 speed or 10 speed gearing while still fitting into 135mm dropouts.

I'm a big fan of the RH212 if you don't need all the power the leaf has, but, i'm thinking if you're in Australia, you may not like the shipping costs.

RH212 Fast Wind

How well does the aluminum case on those hold up compared to the Leafbike? Do you think the RH212 could take 4kW peak for 1 minute?
 
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I agree. CSIRO had a ~97% efficient hub built in 2011. The cost to produce it was $10k and everything back then was done by hand.

Multiple motor factories wouldn't have to build said motor by hand, they have machines that can do it. The materials are no longer unobtanium either. You could mass produce those for a good profit now. But nobody interested in taking the initiative & risk.

How well does the aluminum case on those hold up compared to the Leafbike? Do you think the RH212 could take 4kW peak for 1 minute?

I hear it's pretty good, when they reinforced it after v1, the motor weight went up by 2lbs. They might have overshot the goal on the strength.

@Cowardlyduck has high power adventures on that motor and i think his power input record is 6 or 8kw.

The motor is a bit less efficient than a leafbike 30mm wide stator though so if you're going for efficiency above all, i'd still pick the leaf.

I still like the RH212 because the extra tallness and couple extra stator poles gives it better efficiency and torque output in the low end. If you tell me you have a 90" rear wheel and can't step down to 26", i'd recommend that motor over the leaf. But if we're talking small wheel + high RPM, the leaf will kick it's ass in the efficiency department. less poles then becomes an advantage.
 
It was the Leaf I ran at over 8KW, not the 212. To do that on the Leaf without melting it I through every available cooling mod at it at once except water cooling.

I regularly run the 212 at around 3.5KW. Done with both a STD and Fast winds successfully. Just use some FF and temp monitoring. Literally just rode to work on it at around 3.3KW, through tight/twisty/rough single track in the Aussie bush, up some very steep/long hills (20%+) hit over 100C and all is good. :) Do it every day. :D
If I had hubsinks and thicker phase wires on the 212 I would be comfortable running it at over 5KW. I run 14S, so at 3.5KW that's roughly 65A peaks. Apparently the L10 connector can handle 100A, so theoretically at the 72V this motor is rated for you could run it at 7.2KW. I'm sure that would work for very brief runs with good cooling/ambient temps, but would be annoying to manage keeping it from overheating at that level.

I did have one 212 crack a side cover and shell early on, but Grin replaced that under warranty and never had an issue since running 3 of them in different bikes. That was a manufacturing issue as detailed here:
Cracked CasingsThe first production batch of these motors was a bit vulnerable to cracking right along the rotor shell, especially with high tension wheelbuilds. It seems that the stress on the motor flanges could be high enough to crack open the die casting. In 2019 Nine Continent updated the mold tooling so that the metal was thicker in the shell, which all be stopped these incidents but also added about 400 grams to the total mass.

Cheers
 
My bad!
Yeah the L10 wiring and connector are a big choke point. the rating of the phase pins is <90A. Wondering, do your cables get hot?

I ran mine around 2kw for a while and noticed the motor barely got warm, impressive, so i think it could handle a lot.
 
Apparently the L10 connector can handle 100A
On the All Axle manual Grin warns that the plug melts around 60-70 continuous amps:
Note that this table is based on the motor itself and does not include limitations that may come from the L1019 connector or the controller. The 5 minute power ratings involve phase currents that exceed 60-70 amps and will potentially melt the L10 plug, likely well before the motor itself becomes overheated.
 
I did have one 212 crack a side cover and shell early on, but Grin replaced that under warranty and never had an issue since running 3 of them in different bikes. That was a manufacturing issue as detailed here:
Cracked CasingsThe first production batch of these motors was a bit vulnerable to cracking right along the rotor shell, especially with high tension wheelbuilds. It seems that the stress on the motor flanges could be high enough to crack open the die casting. In 2019 Nine Continent updated the mold tooling so that the metal was thicker in the shell, which all be stopped these incidents but also added about 400 grams to the total mass.

Cheers

One thing I don't like about the RH212 motor is that despite the narrow 35mm distance between spoke flanges it has a 26/74 spoke tension imbalance:

1727914508776.png
In contrast, the GRIN hub has a much greater 49mm distance between flanges yet has a much better 34/66 spoke tension imbalance:

1727914561454.png24/76 spoke tension imbalance means the drive side spokes will be at 2.85 times higher tension than the non drive side spokes. In contrast, the 66/34 tension imbalance on the GRIN motor means the drive side spokes will be at 1.94 times higher tension than the non drive side spokes.

P.S. For the GRIN hub I do wish they would offer a triplet lacing option. With triplet lacing the drive side spokes would have ~97% the tension of the non drive side spokes though the non drive spokes would be now be radial.
 
@Cowardlyduck - what controller are you using in these high power applications.
Phaserunner....it's right at it's limit's, and I used to overheat it until I heatsinked it to my frame with thermal padding. Hasn't overheated once since.

My bad!
Yeah the L10 wiring and connector are a big choke point. the rating of the phase pins is <90A. Wondering, do your cables get hot?
Not that I've noticed, but I can't say I really check that much. Probably what helps in my case is the connector and cables are on the outside edge of my swing-arm. So they are getting constant fresh airflow.

On the All Axle manual Grin warns that the plug melts around 60-70 continuous amps:
That's good to know! I only ever really hold 60+ amps for 10-20 seconds max on the worst hills. Riding on a 20" rim, almost nothing will keep it bogged down once it starts moving a bit and the phase runner ramps into it's power curve so I never see 60+ amps until i'm already moving at around 5-10kph anyway.

@ebike4healthandfitness Interesting info on the spoke tension. That could partially explain the cracking on the early models....i.e. they didn't factor in the stress differences the dishing caused and just made both side covers the same.

This all reminds me....my 20" Allex rim the 212 lives in is horrendously out of balance. I can say ahhh and get an acoustic wobble to my voice while riding. :mrgreen:

Cheers
 
I agree. CSIRO had a ~97% efficient hub built in 2011. The cost to produce it was $10k and everything back then was done by hand.
I wonder what innovations were responsible for this level of efficiency? How hard would it be to implement these things?
 
I wonder what innovations were responsible for this level of efficiency? How hard would it be to implement these things?

Well first off, it's an axial flux motor.. these are typically more efficient than the radial motors we run..
The end turn losses are probably extremely minimal and it's also likely they used the highest grade materials they could get their hands on at the time.

1727923881875.png

1727924929025.png

Mass in in kg

It's a balls to the wall design!

There's a paper if you're interested in reading:
https://renew.org.au/wp-content/uploads/2018/12/marand_high_efficiency_motor.pdf
 
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I agree. CSIRO had a ~97% efficient hub built in 2011. The cost to produce it was $10k and everything back then was done by hand.

Multiple motor factories wouldn't have to build said motor by hand, they have machines that can do it. The materials are no longer unobtanium either. You could mass produce those for a good profit now. But nobody interested in taking the initiative & risk.



I hear it's pretty good, when they reinforced it after v1, the motor weight went up by 2lbs. They might have overshot the goal on the strength.

@Cowardlyduck has high power adventures on that motor and i think his power input record is 6 or 8kw.

The motor is a bit less efficient than a leafbike 30mm wide stator though so if you're going for efficiency above all, i'd still pick the leaf.

I still like the RH212 because the extra tallness and couple extra stator poles gives it better efficiency and torque output in the low end. If you tell me you have a 90" rear wheel and can't step down to 26", i'd recommend that motor over the leaf. But if we're talking small wheel + high RPM, the leaf will kick it's ass in the efficiency department. less poles then becomes an advantage.
It is worse than that....the RH212 has a 27mm stator: RH212 Standard Wind

If everything else was the same, you'd only have 27/35 as much power capability just due to the narrower stator.

I can't recommend any motor that has a stator narrower than 35mm unless somebody has a unique situation...like they can't go to a smaller diameter wheel and they have to run higher amperage for whatever reason then the RH212 might be a good choice...like you said.

I can't think of any reason why somebody would want to go with a narrower stator than 35mm since motors like the Leaf can accommodate at least a 7 speed freewheel/cassette in a 135mm dropouts. Even if you can't use a small diameter wheel, I'd personally still go with a Leaf.

Those L10 connectors are super convenient but the best ones are rated for 45A so not very useful for most of us.

Stators wider than 35mm...lots of good options out there but I am a little partial to the Crystalyte H55xx (55mm stator) series if you want lighter weight or a QS205 (50mm stator) if weight is not as much of an issue and you really want to push some amperage :).
 
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