Leaf / leafmotor / leafbike high efficiency 1500w motor

[madin88]

this bearing does not have protection against water, but if you do not ride in wet conditions or plan to wash your bike with the garden hose, it probably may work well.

talking about drag between normal and sealed bearings is an interesting thing, but i bet it will not be much watts. maybe 5W?
i believe 0,1bar less air pressure in the tires probably would be more noticeable than this..
on many bearing types we can choose between strong seal and normal seal. the normal seal type has less drag (almost as low as these bearings with metal covers) and offers still protection against water.

 

[speedmd]

What is inside the bearing will make much more difference than the seal. These guarded type bearings will seal well with the addition of a outer washer/ water proof grease that overlap / fill the gap in the bearing guard if there is room for one.

 

[Kodin]

Did you have the 2mm or 3mm phase wires?

 

[madin88]

What is inside the bearing will make much more difference than the seal. These guarded type bearings will seal well with the addition of a outer washer/ water proof grease that overlap / fill the gap in the bearing guard if there is room for one.

does the leaf have such additional radial shaft sheal? mxus motors have them for instance, but there is still a bearing with rubber or plastic sealing (rs type) in them.
such high efficient low drag bearings are great for high rpm applications, but how big will be the effect when we use them at very low rpm like our hubmotors have?
IMO it would be more useful to use bearings with the highest cdyn or cstat values and with good sealing against the elements instead of looking for the lowest drag types (but they may also have as good dyn and stat values as others). At least thats what i do when upgrading bearings on my hub motors..

 

[Allex]

I usually buy theese rubber sealed:
http://www.ebay.com/itm/6204-2RS-SKF-Ball-Bearing-20x47x14-mm-6204-2RSH-C3-6204-2RS1-/221819763554?hash=item33a57cfb62:gnQAAOSwT6pVm-5N

 

[Cowardlyduck]

LOL, didn't mean to start a debate on bearings. The metal shielded bearings have been fine for me in all kinds of muddy, dusty and dirty use. I even rode through a flooded creakwith them without any issue.

I think the bearings in our hub motors are more protected than we realise cause on one side they have the side cover recess and on the other side is the axle keyway. There is not a whole lot of room for crap to get it there TBH, and if it does the bearing is not sitting at the bottom of the motor so more than likely anything substantial will fall away.

Did you have the 2mm or 3mm phase wires?

3mm. I could see plenty of room around the wire sitting in the axle hole also, so more than enough room for me to do an upgrade to 12awg silicone wire (silicone replaced by heat-shrink) and add the extra 1 18awg wires for my fan cooling setup.

Cheers

 

[liveforphysics]

I dyno'd it today. Will hopefully have time to edit the videos together tomorrow. It made a peak of 4.9hp output when feeding it ~8kW input. It's pretty efficiency from 500w to 2000w, falls off pretty sharply in efficiency above ~3500w input.

Also, adding ferro-fluid to it makes it run substantially cooler core temps while chugging away at 3kW.

 

[Allex]

Was it messy with the ferro Luke?

 

[madin88]

at what phase amps it started to fall off sharply or what was the torque/thrust at this point?

 

[gensem]

I dyno'd it today. Will hopefully have time to edit the videos together tomorrow. It made a peak of 4.9hp output when feeding it ~8kW input. It's pretty efficiency from 500w to 2000w, falls off pretty sharply in efficiency above ~3500w input.

Also, adding ferro-fluid to it makes it run substantially cooler core temps while chugging away at 3kW.

Luke, playing with Justin trip simulator (MX4503) it does seems that ff only helps some with low power/speed (under 3kw) when you pump like 10kw drilling both covers is the way to go. Does your dyno stand have a pretty strong wind tunnel?

 

[Punx0r]

I dyno'd it today. Will hopefully have time to edit the videos together tomorrow. It made a peak of 4.9hp output when feeding it ~8kW input.

Am I right in thinking your 9C with "flaming dicks" made ~10HP @ 10KW input?

 

[neptronix]

I dyno'd it today. Will hopefully have time to edit the videos together tomorrow. It made a peak of 4.9hp output when feeding it ~8kW input. It's pretty efficiency from 500w to 2000w, falls off pretty sharply in efficiency above ~3500w input.

Does it peak in efficiency at 1000W like the dyno graph says? at that wattage ( ~30mph ), i feel like i can go forever..
3000w is when the efficiency starts to get bad for me at 45mph and it starts making the kind of heat that an old 9C would at 1500W.

Also, adding ferro-fluid to it makes it run substantially cooler core temps while chugging away at 3kW.

Would you say there are any downsides to running ferrofluid? if i could reseal my leaf and run 45mph ( 3kw ) constant, that would be badass.. i'm wondering what the max continuous wattage is with ferrofluid.. any way of testing?

Shit, i'd throw you $25 if you just found out for me.

 

[Allex]

Justin is testing the ferrofluid now so why not ask him I have like 120bucks now from people that want this motor@justins

 

[Cowardlyduck]

After a lot of confusing emails back and forth, it turns out Leafbike don't have any side covers for me with out cracking. This is the last email I got from them:

All new covers fit for your motor,all have cracks.

This crack will not effect anything. No any load on this cover.

No crack cover isn’t fit for your motor.

Either it genuinely won't effect anything as they say, or they do not expect people to be pedalling very hard.

I'm getting them to refund my money and not going to bother with a replacement side cover.

I'm just going to drill my current cracked one and hope for the best.

Cheers

 

[speedmd]

Sounds like the new supplier is not up to the task and they are stuck with a bunch of ugly parts. Hopefully it lasts forever. If not, don't be surprised. They were warned.

 

[liveforphysics]

I dyno'd it today. Will hopefully have time to edit the videos together tomorrow. It made a peak of 4.9hp output when feeding it ~8kW input. It's pretty efficiency from 500w to 2000w, falls off pretty sharply in efficiency above ~3500w input.

Does it peak in efficiency at 1000W like the dyno graph says? at that wattage ( ~30mph ), i feel like i can go forever..
3000w is when the efficiency starts to get bad for me at 45mph and it starts making the kind of heat that an old 9C would at 1500W.

Also, adding ferro-fluid to it makes it run substantially cooler core temps while chugging away at 3kW.

Would you say there are any downsides to running ferrofluid? if i could reseal my leaf and run 45mph ( 3kw ) constant, that would be badass.. i'm wondering what the max continuous wattage is with ferrofluid.. any way of testing?

Shit, i'd throw you $25 if you just found out for me.

This dyno only measures to 0.1hp resolution. If you want to measure efficiency meaningfully at 1hp, you need to use a dyno that can see low power precisely like Justins.

As far as being 3kW stable just by adding FF, ehh, it's at least 5-10min stable at 3kW with FF vs like 2min stable before FF. That's pretty big alone.

Yes, FF stains and is messy to work with. However, I didn't bother to seal this motor at all, simply drilled it and added it and taped over the hole. Like Justin mentioned, it seems to want to live in the highest flux locations between magnets, and I don't think it was even dripping out or weaping anywhere, but it was midnight and I wasn't looking that carefully.

[youtube]WZnYc654Nps[/youtube]

 

[Cowardlyduck]

Thanks for doing this Luke.
I keep saying it, but it's worth saying again. These motor's might not have the torque of a 40, 45, or 50mm wide magnet motor, but they are so much lighter and more efficient than most that they make up for it.
With adequate cooling, I think these Leaf motor's will do great in the 3-4KW burst range.

Cheers

 

[liveforphysics]

Thanks for doing this Luke.
I keep saying it, but it's worth saying again. These motor's might not have the torque of a 40, 45, or 50mm wide magnet motor, but they are so much lighter and more efficient than most that they make up for it.
With adequate cooling, I think these Leaf motor's will do great in the 3-4KW burst range.

Cheers

Agreed. Its a direct drive motor that is neary transparent with pedaling. Works well for getting from A to B, Im happy with its performance for my wifes bike.

 

[Samd]

With adequate cooling, I think these Leaf motor's will do great in the 3-4KW burst range.

Cheers

Has anyone sent one to Justin for testing? I'm curious as to how much power is converted to kinetic energy over the 3500 watt mark. I'm guessing at say 4000 watts the extra 500 watts would be about 100/400 between motion/heat Luke?

 

[madin88]

Thank you Luke. That was the 5T, 35mm Leaf, right?
Any words about the current (when it started to saturate) or what was the core temp before and after FF?

I think it would be better to talk about phase current instead of kW, because kW will vary ALOT depending on wheel size. but i can understand you want the bike to look like a bicycle (with its more comfortable handling), not like a scooter blend

 

[Lurkin]

Is there any way to use a cassette with the freewheel version of this motor? I wanted the strength of the freewheel versions axle, but starting to think I would rather have rear gears if possible. Any ideas? Otherwise its new motor time.

 

[liveforphysics]

Thank you Luke. That was the 5T, 35mm Leaf, right?
Any words about the current (when it started to saturate) or what was the core temp before and after FF?

I think it would be better to talk about phase current instead of kW, because kW will vary ALOT depending on wheel size. but i can understand you want the bike to look like a bicycle (with its more comfortable handling), not like a scooter blend

Yes, 5T 1500W leafmotor.

It was already midnight and I most excited to get thermal baselines to compare to adding FF. Perhaps this weekend it will work out to increase phase current and plot saturation.

If you know what part the thermistor is in the LEAF motor, the video shows you it's resistance that you can correlate to temperature from a look-up chart.

 

[madin88]

If you know what part the thermistor is in the LEAF motor, the video shows you it's resistance that you can correlate to temperature from a look-up chart.

are this the blue numbers on that white gadget near the bike?

 

[Allex]

With adequate cooling, I think these Leaf motor's will do great in the 3-4KW burst range.

Cheers

Has anyone sent one to Justin for testing? I'm curious as to how much power is converted to kinetic energy over the 3500 watt mark. I'm guessing at say 4000 watts the extra 500 watts would be about 100/400 between motion/heat Luke?

I do collect some money to send one out to Justin. If any one wants to add more, it is not too late!

 

[liveforphysics]

If you know what part the thermistor is in the LEAF motor, the video shows you it's resistance that you can correlate to temperature from a look-up chart.

are this the blue numbers on that white gadget near the bike?

Yes.