Leaf / leafmotor / leafbike high efficiency 1500w motor

For the 42mm motor leaf includes a 48v to 72v 60 amp controller (with the option of 80 amp controller). I presume the 80 amp is for those that want to run 48v but still come within ~ 90% of the power of the 72v 60 amp configuration.

So yeah, 40 amp is obviously conservative when we consider the 42mm motor only has a stator width 20% greater than the 35mm yet provides the option for double the amps.
 
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Bullfrog said:
Another decent youtube video on programming the S830 display:

For the wheel diameter...did you guys use inches and the actual outside diameter of the tire? I am running a 26x2.5 Maxxis Hookworm that is 27.0" OD but the speed displayed seems slow.

Once I get my wheel size set correctly, I'll do the speed test with the rear wheel off the ground. Excellent idea to check the Kv :).
Click to expand...

What Kv does the 4T work out to be?

According to the bikes.ca motor calculator Kv 14 for Leaf 1500w 48v using 40 amp controller and 27" tire gets you 34.6 mph with the battery putting out 40 amps.

In contrast, the same combination using Kv 10.49 (Leaf 5T) only gets 31.8 mph with the battery only putting out 30 amp.

So yeah, it could be Leaf sent you the 5T on accident.
 
gromike said:
Then what controller would you recommend for this motor?
Click to expand...

If we're talking about a 4T in a 26" wheel at 48v, the fun starts at 60A and ends at 80A because you can't keep the front wheel on the ground anymore.

You will want a controller that's programmable so that you can set the phase amp to battery amp ratio appropriately so that you get just the right amount of torque from a stall ( enough to blast off, not enough for a wheelie )

I like my old infineon clones with the 3 speed switch and programmability. MAC motor still sells them:
Accessories For Sale | MAC

For a max of 60A, you can get away with a 12FET with 3077 FETs if you beef up the traces and battery input.
Otherwise for 80-100A i would go with an 18FET.

Make sure to get a programming cable and 3 speed switch. I can supply the programming software if they won't provide it.

Otherwise there's lots of newer controllers you could use, but i don't have experience with them.
 
ebike4healthandfitness said:
What Kv does the 4T work out to be?

According to the bikes.ca motor calculator Kv 14 for Leaf 1500w 48v using 40 amp controller and 27" tire gets you 34.6 mph with the battery putting out 40 amps.

In contrast, the same combination using Kv 10.49 (Leaf 5T) only gets 31.8 mph with the battery only putting out 30 amp.

So yeah, it could be Leaf sent you the 5T on accident.
Click to expand...
Supposedly the 4T leaf has a Kv=13.12. Can't remember exactly where I got the number but it was from a reliable source at the time...might have been something that @neptronix posted a long time ago :).
 
gromike said:
Then what controller would you recommend for this motor?
Click to expand...
If you want something relatively inexpensive, light, efficient, reliable, configurable, regen-capable, and good all around, a Grin Baserunner or even a Phaserunner are both excellent choices. You won't be winning races against cars with these, but they're well-suited to being used on a daily basis.
 
Bullfrog said:
Supposedly the 4T leaf has a Kv=13.12. Can't remember exactly where I got the number but it was from a reliable source at the time...might have been something that @neptronix posted a long time ago :).
Click to expand...

Kv 13.12 would do well. When I plugged in Kv of 13 into the calculator I remember it only being a little bit slower than Kv of 14.
 
gromike said:
Then what controller would you recommend for this motor?
Click to expand...
I can't help you on controllers but if I had it to do over again, I'd buy a 4T Leaf 1,500w Freewheel motor and lace it in a 24" SE Bikes J32S rim with Sapim "Race" spokes: Race | Sapim and Sapim Polyax nipples: Polyax | Sapim. I'd also run a Schwalbe 24x2.6" tire.

The smaller diameter rim/tire will give you more thrust/acceleration and it will also help keep your motor from over heating. The tire OD determines the overall gearing for your motor.

Depending on the amperage you plan to run, you could add Statorade and Hub Sinks.

With the 4T motor and the 24" wheel, if you run a 52v battery and a controller that limits your battery current to 40A, your top speed on level ground will be around 35 mph and your motor temperature should stay in the acceptable range without pedaling any unless you start climbing some steep/long hills. I used the Grin Tech Motor Simulator to come up with that information and I plugged in the RH212 with a Kv=13.12 to check the temperatures...the RH212 is the closest motor I could find in the drop down menu to the Leaf motor.

This link is to the simulation: Motor Simulator - Tools
 
Speaking of phase amps.

How many amps would be needed to completely eliminate any advantage a 7 speed pedal drive train has over a single speed pedal drive train. Assume gearing on both systems is not too high as to be of limited benefit (re: pedaling at 90 rpm at high speed carries a substantial drag penalty compared to not pedaling).
 
The Toecutter said:
If you want something relatively inexpensive, light, efficient, reliable, configurable, regen-capable, and good all around, a Grin Baserunner or even a Phaserunner are both excellent choices. You won't be winning races against cars with these, but they're well-suited to being used on a daily basis.
Click to expand...

Boy, that would be really weak on the Leaf 4T.

Max continuous phase amps on the baserunner is 55A.
Phaserunner? 90A ( and overheats if you do that continuously )
I was running 200A phase current on my leaf.

The 4T guzzles amps and is unimpressive on 40A battery. Both of the controllers from grin only output 35A batt continuously. They're essentially the equivalent of a 9FET infineon.
 
Yeah as mentioned previously I was pushing 8KW peaks into my Leaf with active cooling. That was a 4T leaf and running it from an Adaptto Mini-E pushing about 120 battery amps (@66V) and 250 phase amps. It got hot fast, but with that much power I was typically up to speed so fast it didn't matter. Only going WOT on the longest steepest hills did it ever crack 121C/ 250F and need to cool down.

IMO the sweet spot for these with FF and hubsinks would be around 80-100 battery amps and 200 phase on 60-80V. More is fun, but a melted motor isn't so unless going with active cooling, I would suggest staying below those limits.

Cheers
 
neptronix said:
Boy, that would be really weak on the Leaf 4T.

Max continuous phase amps on the baserunner is 55A.
Phaserunner? 90A ( and overheats if you do that continuously )
I was running 200A phase current on my leaf.

The 4T guzzles amps and is unimpressive on 40A battery. Both of the controllers from grin only output 35A batt continuously. They're essentially the equivalent of a 9FET infineon.
Click to expand...
My Phaserunner was very usable on a Leaf 4T in a 26" wheel at 1500W/96A. It wasn't very fast, but it was enough to keep up with traffic just fine, with enough reserve power to get out of trouble if it comes my way. But my application was a DIY velomobile capable of 45+ mph in that configuration.

10kW/200A with an ASI BAC4000 was enough to blow the doors off a V6 Dodge Charger at a stop light up to about 30 mph, but that was with a new 3T motor in a 20" wheel.
 
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chuyskywalker said:
Since the leaf experts are in here :), when you order something from their site, such as this rear motor, and they offer different "speed" versions -- is that them actually giving your a different winding?
Click to expand...
Yes. They wind motors to order. There are default windings if you don't specify, but they'll wind any number of turns that applies to what you're doing.

Note, high winding count doesn't change the maximum torque you can get from a motor, which is a function of motor architecture and copper fill percentage. But it can greatly increase the torque available from a given controller, and it can move the power and efficiency peaks of the motor to where they better match the properties of the vehicle.

Low winding counts have the highest power potential, but only by using high RPM and high current controllers that can be exotic and expensive.
 
See the first couple pages for backstory, but..

The default winding ( 4T ) will do about 40mph in a 26" wheel on 48v, so it'll chug amps ( 40-80A ) to make max torque and speed. Most prebuilt packs cannot handle this, you need a pack that is above and beyond beefy ( i used RC Lipo on mine! )

5T in the same condition will do ~32mph on 48v, you'll want a beefy ( 20ah+ ) pack still. Run 52v and you're up to 35mph.

For a refresher, here's how my 4T on 10AH 72v 20C RC Lipo performed:

 
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I wonder if some people in this thread would be better served by the narrower (27mm/28mm ?? wide stator) leaf bike motor (i.e. the one rated 750w at 36v and 1000w at 48v).

First of all it is still 90.5% efficient like the 35mm. Secondly, the 7 speed freewheel version is a true 135 mm and also makes a dish-less wheel (although the distance between spoke flanges (at 35mm) is 5mm less than the distance between flanges on the 35mm motor which is 40mm).

Still because the wheel is dish-less the risk of spokes loosening after hitting a hard bump is going to be much lower than what you would see with the 35mm 7 speed freewheel version. Major Downside though to narrower distance between spoke flanges is reduced lateral stiffness. That means the dished 35mm 7 speed wheel will be more laterally stiff than the dish-less narrower motor 7 speed wheel as long as none of its spokes have gone loose. However, if the dished 7 speed 35mm begins suffering from loose spokes then it's lateral stiffness advantage goes away. This because loose spokes do not contribute to lateral stiffness. Indeed with enough loose spokes the dished 35mm 7 speed wheel would become less laterally stiff than the dish-less (27mm/28mm?? wide stator) 7 speed freewheel motor.

My biggest concern though is phase wire diameter. Neptronix's 35mm wheel he bought back in 2015 had puny 18 guage phase wires. Does the narrow (I assume 27mm or 28mm wide stator) motors have these as standard equipment in 2024? Or do they come with something thicker?

I did send Leaf Bike an inquiry on the diameter of the 36v 750w/48v 1000w motor phase wire diameter.
 
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Found out the narrower stator motor (described in the post above) is not 27mm or 28mm wide......but is instead 30mm wide!

Wow!

P.S. Still waiting to find out the diameter of the phase wire. (Edit: Leaf Bike says the 30mm motor has 2mm phase wire which is 1mm less than the 3mm phase wire usef by the 35mm and 3mm less than the 5mm phase wire used by the 42mm motor).
 
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ebike4healthandfitness said:
Found out the narrower stator motor (described in the post above) is not 27mm or 28mm wide......but is instead 30mm wide!

Wow!

P.S. Still waiting to find out the diameter of the phase wire. (Edit: Leaf Bike says the 30mm motor has 2mm phase wire which is 1mm less than the 3mm phase wire usef by the 35mm and 3mm less than the 5mm phase wire used by the 42mm motor).
Click to expand...
Good info, Thanks.

I didn't realize the bigger motor came with 5mm phase wires...that is pretty impressive.

So all other things being equal, the wider stator should produce 42/35 times as much torque per amp. Personally...if my 35mm Leaf gets boring, I plan to go with a Crystalyte H+55100 motor.
 
neptronix said:
If we're talking about a 4T in a 26" wheel at 48v, the fun starts at 60A and ends at 80A because you can't keep the front wheel on the ground anymore.
Click to expand...

So if the 35mm can handle up to 80 amps at 48v where does that leave the 30mm leaf bike motor?

Certainly the 45 amp at 48v/52v 1500w to 1800w leaf bike controller wouldn't be too much for the 30mm wide stator motor right?

www.leafbike.com

48V 52V 1500W 1800W electric bike motor controller

The leaf 48V 52V 1500W 1800W bike motor controller is so easy to drive your electric bicycle.
www.leafbike.com www.leafbike.com
 
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Look at the dyno sheet for the 30mm model..
86.2% efficient at 23A, and dropping beyond that

35mm model..
85.3% efficient at 49A, and dropping beyond that

This would imply the 30mm is doing poorly at 40A.
It's a totally average motor and the 90.5% efficiency peak on the 30mm looks like either a lie or a fluke.

Wouldn't recommend that motor at all, for another 2lbs you get a lot.

As for phase wires.. my 1500W from 2014 came with a pathetic gauge.. i cut the motor wires an inch out of the axle and installed 12ga wires.. no problem. Newer models have a thicker gauge.
 
ebike4healthandfitness said:
I wonder if some people in this thread would be better served by the narrower (27mm/28mm ?? wide stator) leaf bike motor (i.e. the one rated 750w at 36v and 1000w at 48v).
Click to expand...
Probably not, but maybe if you start another thread: "Leaf / leafmotor / leafbike high efficiency 1000w motor"
 
neptronix said:
Look at the dyno sheet for the 30mm model..
86.2% efficient at 23A, and dropping beyond that

35mm model..
85.3% efficient at 49A, and dropping beyond that

This would imply the 30mm is doing poorly at 40A.
Click to expand...

If you took the 35mm motor and coupled it to a such a weak controller like the 30mm is using its efficiency would peak at low amps and then also drop.

The only way to truly compare these motors is to use the same Kv, same wheel diameter, same volts and same amps with a strong enough controller.

Only then could you tell the true thermal limits of each of motor.
 
E-HP said:
Probably not, but maybe if you start another thread: "Leaf / leafmotor / leafbike high efficiency 1000w motor"
Click to expand...

No need to start another thread. If the Leaf 30mm (which has .35mm laminations) models at least as good as the Nine Continent 30mm it would be plenty of motor for most people using the 48v 40 amp controller that comes in the Leaf 1500w kit.

See results below using a 26" wheel and the fastest winding available for the Nine Content 30mm (the 3004, which has Kv of 13.94):

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 ebikes.ca
 
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