Leaf / leafmotor / leafbike high efficiency 1500w motor

[ebike4healthandfitness]

The side covers are typically aluminium. Only the stator support and magnet ring are steel.

This posts claims leaf bike 1500 watt spoke flanges and middle part are steel:

Using leafmotor/leafbike 1500w as mid-drive motor?

Is there any reason why I cannot or should not buy a 1500w rear spoke motor from leafmotor/leafbike and mount a sprocket onto the 6 bolt threads for the disc brake for use as a mid drive motor on a velomobile project? What are the threads on the opposite side for? mounting a casette...

endless-sphere.com

 

[amberwolf]

How did you attach those heat sinks? I’m doing the same thing and was planning on using thermal glue. I’m putting some thin strips of two way thermal tape near the edges to hold them in place while the glue sets.

I'd just use zipties, inserted into each other in series to make them as long as necessary, as a band around the heatsinks on the rotor to secure them down.

If you really want to clamp them on good and hard while it sets to force them as hard as possible against the metal for best conduction, I'd use a big hose clamp, but it would be a PITA to tighten down the screw if the motor is already laced into a wheel. :/

 

[Cowardlyduck]

This posts claims leaf bike 1500 watt spoke flanges and middle part are steel:

Using leafmotor/leafbike 1500w as mid-drive motor?

Is there any reason why I cannot or should not buy a 1500w rear spoke motor from leafmotor/leafbike and mount a sprocket onto the 6 bolt threads for the disc brake for use as a mid drive motor on a velomobile project? What are the threads on the opposite side for? mounting a casette...

endless-sphere.com

Correct, they are. As stated, it's the side covers that are aluminium.

 

[ebike4healthandfitness]

Maybe it is just a longstanding preconception but I personally am still uncomfortable with the idea of housing the heat-sensitive batteries inside a heat-producing motor enclosure. Unless maybe they have devised some form of high-functioning insulation? Same for the heat-sensitive controller components.

For the P110 motor (which is the same motor used by both the P130 and P160) the gave it a rating of 750 watts despite its smaller hubshell.

With both the P130 and P160 they added a larger hubshell to house the batteries/controllers/sensors, etc while at the same time lowering power from 750 watts to 350 watts and 400 watts respectively.

 

[Bullfrog]

I just don't like the way they look, so I'm willing to deal with the hassle. I'm only looking for -5C, if possible.

Your experience saves me a lot of headaches. I was on the fence about the safety wire.

One option...you could cut down the fins on the Heat Sinks. Keep in mind the amount of heat transfer is proportional to the fin area so the sinks that CowardlyDuck used won't help as much as a set of cut down Heat Sinks that Grin sells. But I totally understand wanting to get the "look" you are after.

Another option is to buy some powdered Aluminum or Copper and mix it in with whatever Epoxy you want to use. As far as conductivity, the highest is Silver, then Copper, then Gold, then Aluminum. Silver and Gold are a little too pricey and Copper isn't cheap, heck even Aluminum has gotten expensive.

I looked into thermal RTVs way back when "Luna Cycles" was looking to produce aftermarket controllers for the BBSHD but I can't remember exactly what I found....just another thing that sucks about getting old .

 

[Bullfrog]

I'd just use zipties, inserted into each other in series to make them as long as necessary, as a band around the heatsinks on the rotor to secure them down.

If you really want to clamp them on good and hard while it sets to force them as hard as possible against the metal for best conduction, I'd use a big hose clamp, but it would be a PITA to tighten down the screw if the motor is already laced into a wheel. :/

I like the hose clamp idea and you could put more than one together if you can't find one that is long enough plus they are easily removed...maybe two hose clamps, one on each edge.

McMaster Carr has a good selection of hose clamps and zip ties...this link is to their zip ties: McMaster-Carr

Here is one for their hose clamps: McMaster-Carr

 

[E-HP]

I'd just use zipties, inserted into each other in series to make them as long as necessary, as a band around the heatsinks on the rotor to secure them down.

Thanks. With some searching I was able to find some black 0.10” width zip ties, 18lb strength, that should fit down the center slots of the heat sinks. 2 cents each, but 100 minimum.

 

[Bullfrog]

DECISIONS ALREADY MADE: I decided to go with Statorade and Hub Sinks from Grin Tech (ordered and on the way). I also decided I am going to run a Schwalbe Pick-Up tire in size 24x2.6" tire when I get my motor laced in a 24" rim...it is currently in a 26" rim and I plan to use the Maxxis Hookworm (26x2.5") until I get everything together to change rims. I was torn whether to drill my side covers or use Statorade and Hub Sinks but Neptronix made a comment at some point about contamination and that helped me fall off of the fence on the Statorade/Hub Sinks side of the fence. In the past I have tried Low Viscosity ATF and a Water/Motul MoCool mixture...they both worked great from a cooling perspective but the ATF leaking via Capillary action through the wires killed my rear brake and the Water mixture evaporated a little quicker than I expected so it always needed topping off. I used both in my MAC and was pushing at slow speeds (bad combination). Since I plan to cruise at 40-45 mph, I plan to start with 12.5ml of Statorade...that way I'll have four fills available in the 50ml bottle I ordered.

QUESTION: What 24" rim would you recommend if I plan to run the 2.6" Schwalbe Pick-Up tire...I am hard on wheels/tires and have weighed as much as 250 lbs so I'd rather cry once when I buy the new rim than cry when I break a cheap one and then cry again when I have to buy a new rim to replace it.

Thanks...I sure do appreciate the help you guys provide. I also sent a couple messages to people on the rim question and I'll post their answers once I OK it with them. I apologize if I have asked the 24" rim question previously...I thought I had but I can't find the conversations. They say your memory is the first thing to go so obviously I am well down the path to old age .

 

[amberwolf]

They say your memory is the first thing to go so obviously I am well down the path to old age .

What were we talking about?

Rims... There's several posts in previous pages that a CTRL-F for " 24" (the space to eliminate 2024) or "rim" finds rim mentions, such as Halo SAS, Alex, Ryde, but whenever I want to know about a wheel part I usually do a search for whatever that part is with Chalo as post author. like this

Search results for query: rim

endless-sphere.com

 

[Cowardlyduck]

I ran my modded leaf in a 24" rim. I re-used the rim that came with my Stealth Fighter after I cooked it's previous motor. No idea what brand/model it was as it had no label, but I can tell you it was double walled alloy and super strong. I also re-used it's super thick spokes. From memory they were 10g, maybe 11g, but super sturdy and strong. Never had any issues with that setup and I rode it super hard.

Cheers

 

[ebike4healthandfitness]

I ran my modded leaf in a 24" rim. I re-used the rim that came with my Stealth Fighter after I cooked it's previous motor. No idea what brand/model it was as it had no label, but I can tell you it was double walled alloy and super strong. I also re-used it's super thick spokes. From memory they were 10g, maybe 11g, but super sturdy and strong. Never had any issues with that setup and I rode it super hard.

Cheers

Nice.

Lots of people think the only way to increase resistance to spoke breaking at the elbow is to use double butted spokes with thin center sections (eg. 14g/15g/14g) but a stiff rim also spreads the load out to more spokes.

 

[Bullfrog]

Thanks for the rim comments.

I did go back and forth with Chalo via a message and he recommended one of the "Ryde Andra 40" and the "SE Bikes J32S"...both available from J&B.

I agree with Amberwolf....Chalo's recommendation carries a good bit of weight, I have never known him to steer anyone wrong and his experience with bikes vastly exceeds most of us including me.

Based on Chalo's recommendation and the fact that the SE Bikes 24" J32S rim is one of the widest available (32mm Internal width), I ordered one a few minutes ago. Only thing I need now is spokes.

 

[ebike4healthandfitness]

Bullfrog,

I know you like torque. In your search for a 1500 watt hub motor did you ever consider a geared hub motor rated at 1500 watts?

MXUS GDR19-FAT - Most powerful geared motor?

Posting in the Bafang forum as there is no MXUS forum, and this motor may be relevant to users of the Bafang geared hubs. This is somewhat of a new motor, and limited information is available in english. Here is some information that may help. XF19R XF19R-FAT GDR19 FAT GDR19-FAT 2 versions of...

forums.electricbikereview.com

 

[chuyskywalker]

I know you like torque. In your search for a 1500 watt hub motor did you ever consider a geared hub motor rated at 1500 watts?

I picked one of these up a while back and I *really* wanted to like it, but I'm pretty sure I got a dud as none of 5 different controllers could get it to run reliably without issuing some form of phase overcurrent. It looks beefy as heck, though.

 

[Bullfrog]

Bullfrog,

I know you like torque. In your search for a 1500 watt hub motor did you ever consider a geared hub motor rated at 1500 watts?

MXUS GDR19-FAT - Most powerful geared motor?

Posting in the Bafang forum as there is no MXUS forum, and this motor may be relevant to users of the Bafang geared hubs. This is somewhat of a new motor, and limited information is available in english. Here is some information that may help. XF19R XF19R-FAT GDR19 FAT GDR19-FAT 2 versions of...

forums.electricbikereview.com

I have a couple of bikes with MAC motors. The MAC produces more torque per battery amp than any ebike motor currently in the drop down menu of the Grin Tech Motor Simulator and that includes the Leaf, Cromotor/QS205, MXUS, Crystalyte Crown, etc.

I run a peak of 60A battery current to my MAC and have my controller set for 200A max. The MAC puts out almost 200 NM peak. Only problem with a MAC is it is a geared hub motor so there is a relatively big air gap between the stator and the housing which means it will over heat easier than a DD hub motor. I can run 60A battery/200A phase current every time I start from a standstill but steady state you can't run more than about 1,200 watts or it will eventually over heat...of course it takes about an hour to reach 130C if you start out at ambient temperature. As for the gears, I run Mobilith SHC 100 covering the ring gear teeth when I assemble it and I have never had a problem with the plastic/phenolic gears or the clutch.

Thanks for mentioning the Geared Hubs. The MAC and GMAC have 20mm stators...there was a version of the MAC called a Big MAC (just like the burger from McDonalds) but it never went into production supposedly because it over heated too easily. I'd be afraid the wider MXUS geared hub would be the same way. MACs are super fun to play with because of the 5X torque multiplication but they can be a pain if you don't limit the power to some extent. The GMAC has some good improvements compared to the MAC and the GMAC is also capable of regen.

As far as controllers, I bought my first one from EM3ev.com back when they sold the MAC and then I bought one directly from MAC...they were all Infineon Clones.

 

[Bullfrog]

24" rims...I searched far and wide trying to find a rim that had an internal width greater than 32mm and less than 40mm but I never found anything. I am satisfied with the SE Bikes J32S rim (32mm internal width) I ordered but it is the only 24" rim I found that was wider than 30mm internal width until you jump up to 40mm internal width for the Alex MD40 rim.

24" stuff is just sort of in no man's land between the much more popular 20" and 26" stuff but I chose it because I wanted the smallest diameter tire possible without having to resort to a Radial or Modified Radial lacing pattern.

I got my local bike shop to order the SE Bikes J32S rim from JBI...my cost was $45 plus tax.

 

[ebike4healthandfitness]

Bullfrog,

When was the Big MAC motor in development?

Was this pre 2016? The time when MAC was using .35mm stator laminations?

I see the 1500w MXUS geared hub motor only has 80% efficiency so I assume it is using .35mm laminations. With that noted, I am sure it won't be too long before it has .27mm laminations like MAC.

 

[ebike4healthandfitness]

One thing I really like about Leaf bike is they sell 16",17",18" and 19" moped rims laced to their motors. (You can find these on their website either as a moped rim by itself, a complete moped rim wheel or as a complete moped rim wheel in a kit).

My particular favorites are the BMX kits (110mm rear spacing) using the aluminum moped rims (16" x 1.85" or 19" x 1.85") laced to the leaf bike 35mm motor using thick spokes. Such a wheel is also manufactured dish-less meaning both drive and non drive spokes will be at the same tension.

Being 110mm also means they can also fit on cruisers originally using the ubiquitous Shimano CB-E110 coaster brake hub.

One problem (besides being limited to 16T because of freewheel) exists with these 110mm rear spacing kits, wheels and motors:

They all use 10mm axle flats, and all bmx bikes I have seen either use 14mm axles or 3/8" (9.5mm) axles. Cruisers using coaster brake hubs also use 3/8" (9.5mm) axles

Sure a person could file the 10mm axles down a bit to 3/8" (9.5mm) or file the drop out themselves from 3/8" (9.5mm) to 10mm but most people I reckon will never do this or will be afraid to this to the axle or will not want to open up their dropout slots from 3/8" (9.5mm) to 10mm. Obviously the later will be easier to do than filling down the axle but they may still be concerned about vertical play if ever planning to return back to non hub motor 3/8" axle wheels. You may think .5mm (.02") vertical play is not much but any additional movement (from jumps, hard landings, tricks, etc.) will only lead to extra vibrations contributing to loosening of the nut fastening the axle.

 

[neptronix]

I talked to Paul at em3ev when he was closely working with MAC.
Massive problems controlling it and heat were what prevented the big mac from becoming a thing.
They spent years trying to get it to work.

The lower efficiency of the MXUS makes it a non-starter for me. The MAC is thermally handicapped enough as it is. it's a real bummer MXUS didn't put more quality into it.

 

[ebike4healthandfitness]

The lower efficiency of the MXUS makes it a non-starter for me. The MAC is thermally handicapped enough as it is. it's a real bummer MXUS didn't put more quality into it.

Assuming at 80% efficiency the 1500 watt MXUS could hold 2000 watts. (Not sure if this is true or not I am just using it as an arbitrary example). That means in order to get the 2000 watts it needs 2500 watts input power resulting in 500 watts heat (re: 2500 x .80 = 2000 and 2500 - 2000 = 500).

But let's say we bump efficiency up to 83% from 80% (something I assume is reasonable if going from .35mm laminations to .27mm laminations). Assuming the hub can still reject 500 watts heat continuously the new continuous power becomes 2444 watts. This because 2945 x .83 = 2444.35. The difference between the input power of 2945 watts and the output power of 2444.35 watts (and thus amount of heat rejected) is 500.65 watts.)

So in the above case a small bump in efficiency from 80% to 83% results in a 22.2% percent increase in max continuous power.

 

[neptronix]

It could hold it, but not thermally. Most geared motors can only shed ~150W continuous. Maybe you get really lucky with the MXUS and that figure is 175W.

The motor is already producing 200W of heat at 1200W if this is @ 80% efficiency, there's close to no headroom in this motor rating. Oh sure you can make lots of torque but...

 

[ebike4healthandfitness]

FWIW, I recalculated my example in post #2845 from 2000 continuous watts to 1500 continuous watts and the relationship of boosting continuous power after a bump in efficiency from 80% to 83% remained the same at 22.2%.

This same 22.2% should hold if we recalculate at 1200 continuous watts as well which would result in a new continuous power of 1466.4 watts.

With that noted, Imagine what could happen if they could boost efficiency to 87% or more? I'm not going to do the math but I know it would be a very good increase in max continuous power.

 

[ebike4healthandfitness]

For those interested in "hub mounted heatsinks" this integrated design looks much more efficient:



The hubshell is also likely made of aluminium (like the Grin all axle motor) which would further boost heat transfer when using Statorade. (Steel hubshell + thermal interface material + aluminum hub sinks oriented in an un-aerodynamic fashion and poor airflow fashion to the fins......(as shown below)




......has got to be night and day worse than what we are seeing in the first picture which is a slick (and very likely) one piece aluminum design (i.e. no thermal interface material needed to connect hubshell to cooling fins) with low added weight, great aerodynamics and (very likely) extremely good heat transfer potential when used with statorade.

 

[Bullfrog]

Bullfrog,

When was the Big MAC motor in development?

Was this pre 2016? The time when MAC was using .35mm stator laminations?

I see the 1500w MXUS geared hub motor only has 80% efficiency so I assume it is using .35mm laminations. With that noted, I am sure it won't be too long before it has .27mm laminations like MAC.

I don't know the exact time frame.

 

[E-HP]

For those interested in "hub mounted heatsinks" this integrated design looks much more efficient:

View attachment 351415
......has got to be night and day worse than what we are seeing in the first picture which is a slick (and very likely) one piece aluminum design (i.e. no thermal interface material needed to connect hubshell to cooling fins) with low added weight, great aerodynamics and (very likely) extremely good heat transfer potential when used with statorade.

Since the cooling is integrated into the motor’s design, there’s no need to speculate, since the effectiveness of the design should be reflected in the motor specs, and be used as a selling point. What is the motor rated at, weight, and dimensions, etc.?