Leaf / leafmotor / leafbike high efficiency 1500w motor
- Thread starter neptronix
- Start date
I checked them, what do you not agree with?
The RH212 with a 27mm stator came directly off of the Grin Tech web site and I provided the link where I got it.
Yep, it does indeed only have a 27mm stator....check the rest, read what I previously wrote and don't imply that it can't keep up purely based on stator width....as Nep pointed out, there's more to it than that.
Regardless of stator widths, rotor heights, or any other metric, what counts is how it performs and I can tell you after using/riding and modifying most reasonably priced, high performance hub motors released over the last 13 years the RH212 is a solid performer. It's not the highest performing hub out there, but for the weight and price it is very good. Directly comparable to the 35mm wide Leaf.
Cheers
Regardless of stator widths, rotor heights, or any other metric, what counts is how it performs and I can tell you after using/riding and modifying most reasonably priced, high performance hub motors released over the last 13 years the RH212 is a solid performer. It's not the highest performing hub out there, but for the weight and price it is very good. Directly comparable to the 35mm wide Leaf.
Cheers
The Toecutter
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I look forward to seeing if the Leafbike 1500W 3T in a 20" equivalent wheel can handle 12kW input. With front Grin all-axle motors to help motivate this thing, it should be so quickly out of its torque band at full acceleration that the rear motor may not get hot.
lnanek
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RH212 sure doesn't look comparable to Leaf in the motor simulator:
5mph different, isn't it? If someone goes with that motor instead I'd hope it has a better price point, weight, or fits in smaller drop outs or something. Seems wrong to claim it's comparable in performance, though.
5mph different, isn't it? If someone goes with that motor instead I'd hope it has a better price point, weight, or fits in smaller drop outs or something. Seems wrong to claim it's comparable in performance, though.
Yeah i think it's probably equivalent to a 30mm wide leaf.
It has a few % less cruising efficiency but has an efficiency/torque edge at low RPM.
I'm basing that on the 30mm wide motors on the simulator; imagining the leaf might be a tiny bit better.
In a 24", it really reminds me of the leaf 35mm in a 26" though.. i think it's the immense low end torque.. the magic pie had the same effect, but just wasn't wide enough to handle a lot of continuous power.
It's also got nice aesthetics. I wonder how much the design contributes to helping cool the motor.
It has a few % less cruising efficiency but has an efficiency/torque edge at low RPM.
I'm basing that on the 30mm wide motors on the simulator; imagining the leaf might be a tiny bit better.
In a 24", it really reminds me of the leaf 35mm in a 26" though.. i think it's the immense low end torque.. the magic pie had the same effect, but just wasn't wide enough to handle a lot of continuous power.
It's also got nice aesthetics. I wonder how much the design contributes to helping cool the motor.
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The Toecutter
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A more accurate comparison would b to modify the kV value of the Leafbike motor to a 6T wind. I suspect both will be very close.
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w/winding adjustment
Motor Simulator - Tools
I'm actually surprised by these results, RH212 is a better motor than i thought.
Notice that we're making more torque per amp thanks to the extra diameter and poles.
& we have a minor efficiency difference, but the RH212 is taking this speed just fine.
As usual in 20" wheeled recumbent duty the leaf starts kicking ass in efficiency, the classic 9C stator really shines in small wheels:
Motor Simulator - Tools
I'm actually surprised by these results, RH212 is a better motor than i thought.
Notice that we're making more torque per amp thanks to the extra diameter and poles.
& we have a minor efficiency difference, but the RH212 is taking this speed just fine.
As usual in 20" wheeled recumbent duty the leaf starts kicking ass in efficiency, the classic 9C stator really shines in small wheels:
Well I guess everything is subjective. In my case I ran the Leaf in a 24" wheel with various tire sizes and now I run the 212's in a mix of 20" wheels. So that probably makes up for some of the difference in stator width. That being said, I ran the Leaf side-by-side (2 separate 24" wheel sets) with a Crystalite HS4060 (so 40mm stator width) and the Leaf was able to match it's performance exactly. The Leaf having better copper fill and higher efficiency compared to the Crystalite meant it could keep up just the same.
I stand by what I said, the Leaf motor's (30mm or 35mm) are comparable to the 212. Similar to the situation above comparing the HS4060 to the Leaf, the Leaf vs the 212 is matched by virtue of the 212 having a larger diameter so it doesn't need the 35mm width.
If you had to get specific, in terms of performance, I would say it's 30mm Leaf, then 212, then 35mm Leaf.
But again, none of that matters, numbers don't matter, specs don't matter, what really matters is real world performance and I can tell you the 212 holds up against the Leaf.
There you go, I said I didn't feel like going through it in detail, but now I just did.
Cheers
I stand by what I said, the Leaf motor's (30mm or 35mm) are comparable to the 212. Similar to the situation above comparing the HS4060 to the Leaf, the Leaf vs the 212 is matched by virtue of the 212 having a larger diameter so it doesn't need the 35mm width.
If you had to get specific, in terms of performance, I would say it's 30mm Leaf, then 212, then 35mm Leaf.
But again, none of that matters, numbers don't matter, specs don't matter, what really matters is real world performance and I can tell you the 212 holds up against the Leaf.
There you go, I said I didn't feel like going through it in detail, but now I just did.
Cheers
Recumbent duty with a 30mm 9C stator vs a RH212.
Interesting that the RH212 doesn't take as big of a hit from high RPM as i expected.
Classic 9C stator still shining in this application - we're close to the ideal load point for that motor. We have a bigger torque per amp deficit though.
RH212 does really punch above it's weight!
Interesting that the RH212 doesn't take as big of a hit from high RPM as i expected.
Classic 9C stator still shining in this application - we're close to the ideal load point for that motor. We have a bigger torque per amp deficit though.
RH212 does really punch above it's weight!
The Toecutter
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I'm thinking the RH232 might be able to take a fair bit more than 3.5 kW peak, looking at the comparisons to the Leaf... Maybe upwards of 7-8 kW.
ebike4healthandfitness
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A better comparison would be the fast winding (rather than the STD winding) RH212 to the stock Leaf 5T. Using the same input parameters you used here how that turns out:
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
RH212 vs Leaf....if you power both with 60A (Battery amperage) and 52v, a controller capable of 200 phase amps, and set the Kvs so the top speed is equal on flat ground, the RH will accelerate slightly quicker than the Leaf but it will also run hotter as you increase the amperage so the Leaf will have a little more capability to handle higher amperage. If you keep the battery amperage at 30A or below, I doubt you'll ever notice a difference in actual operation but if you push the amperage above about 30A (battery) then the Leaf's 35mm stator starts to show its advantage over the 27mm stator in the RH by producing equivalent power while running at a lower steady state temperature.
Below is a link to the run I did using the Grin Tech Motor Simulator and the parameters I describe above:
ebikes.ca
Below is a link to the run I did using the Grin Tech Motor Simulator and the parameters I describe above:
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
ebike4healthandfitness
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Too bad we don't have temperature and statorade data on the Leaf 1500w. It would make the RH212 vs. Leaf 1500w duiscussion more interesting.
This because while both motors have the ~same distance between spoke flange centers the leaf has a 30% wider magnet and thus can handle 30% statorade and thus should have a 30% better heat conduction pathway to the back iron part of the hubshell:
The quote below discusses the relationship of heat dissipation to torque.
ebikes.ca
"What does this mean in practice? Well, if you can double the amount of heat that a motor can dissipate, it means (due to the I2R relationship) you can run it at roughly 40% higher sustained torque and power without overheating. 40%! In practice, what this means is that bike rides that used to push your hub motor to 100+°C will now only result in ~70°C temperatures. And when the motor does get hot from a short intense power burst, then it be that much faster at cooling down and being ready for the next thrust of high power."
So yeah, I actually wonder if a Leaf 1500w is a better climber than a RH212 when both are equipped with the optimum amount of statorade.
This because while both motors have the ~same distance between spoke flange centers the leaf has a 30% wider magnet and thus can handle 30% statorade and thus should have a 30% better heat conduction pathway to the back iron part of the hubshell:
The quote below discusses the relationship of heat dissipation to torque.
Statorade - Grin Products - Product Info
Statorade is a specially formulated ferrofluid that improves the thermal performance of direct drive hub motors. Just a small amount added to the motor magnets can double the thermal conductivity of the core, allowing the hubs to be driven harder and longer before risk of overheating.
ebikes.ca
"What does this mean in practice? Well, if you can double the amount of heat that a motor can dissipate, it means (due to the I2R relationship) you can run it at roughly 40% higher sustained torque and power without overheating. 40%! In practice, what this means is that bike rides that used to push your hub motor to 100+°C will now only result in ~70°C temperatures. And when the motor does get hot from a short intense power burst, then it be that much faster at cooling down and being ready for the next thrust of high power."
So yeah, I actually wonder if a Leaf 1500w is a better climber than a RH212 when both are equipped with the optimum amount of statorade.
What you say about heat build up/dissipation is 100% true, but.....you're still completely ignoring/forgetting that these two motors ARE NOT THE SAME DIAMETER!!!
If you assume they are the same size in every regard apart from stator width, then what you have said is correct, but that's not the case! Just take another look at Neps meme above to remind you of that.
Cheers
If you assume they are the same size in every regard apart from stator width, then what you have said is correct, but that's not the case! Just take another look at Neps meme above to remind you of that.
Cheers
In most scenarios, the RH212 is a more efficient climber due to the larger diameter.
On the flat, the Leaf is going to be more efficient across the band, especially if you go to a smaller wheel.
The right motor choice depends on your riding conditions.
That's right, you just got a 'it depends'
What are your design parameters, ebike4healthandfitness? i've never heard you talking about building an actual ebike.
On the flat, the Leaf is going to be more efficient across the band, especially if you go to a smaller wheel.
The right motor choice depends on your riding conditions.
That's right, you just got a 'it depends'
What are your design parameters, ebike4healthandfitness? i've never heard you talking about building an actual ebike.
ebike4healthandfitness
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I know the RH212 is 212mm diameter stator and Leaf Bike is 205mm diameter stator but that difference in diameter is only 3.4%.
ebike4healthandfitness
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It's a better climber for a multitude of reasons no doubt. One of which is the higher (26 vs. 23) pole count. Who knows perhaps it has thicker and/or stronger magnets too as that is another factor that increases torque output at the expense of high RPM efficiency.
Definitely a 3.4% increase in stator diameter is not going to be the sole reason the motor is a better climber. You should have at least mentioned the the increase in pole count when you made your claim.
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ebike4healthandfitness
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No, Pole count is an independent variable from stator diameter.
For example, QS sells a 273mm diameter stator hub motor with only 16 pole pairs:
E Bicycle Hub Motor QS273 V3 Bike Hub Motor
It's E Bicycle Hub Motor QS273 Bike Hub Motor 12000W 40H V3 With 19x1.6inch 19x1.85inch Moped Wheel Rim 100KPH For Electric Bicycle.
www.cnqsmotor.com
@ebike4healthandfitness - come-on man you seem to be trolling more than contributing.
Are you actually planning on using any of these motor for a build? Do you have any build threads?
As mentioned above multiple times, the specs and numbers mean nothing compared to real world usage. Nep and I both have that with these motors and are telling you they are comparable. Take it or leave it. No point trying to convince us our first hand experience isn't real!
Stop being a keyboard warrior, pick something, build something and get out and ride!
Cheers
Are you actually planning on using any of these motor for a build? Do you have any build threads?
As mentioned above multiple times, the specs and numbers mean nothing compared to real world usage. Nep and I both have that with these motors and are telling you they are comparable. Take it or leave it. No point trying to convince us our first hand experience isn't real!
Stop being a keyboard warrior, pick something, build something and get out and ride!
Cheers
Doesn't look like it to me either, but not everybody here builds evidently. It's a big tent.
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