Make a watercooled high kw motor and I'll buy it !

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atarijedi   100 W

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Re: Make a watercooled high kw motor and I'll buy it !

Post by atarijedi » Feb 20 2017 1:16am

Ohbse wrote: I have personally tested both and can assure you my motor was well sealed. Oil permeates everything and wicks along stranded wire, it seeps through bearings, it's impossible to stop completely in conventional hubs.

FF in comparison is mess free and does work as well. It is also much, much easier to clean up.

It may be difficult to imagine, but it's effectiveness has been proven
If it is seeping along stranded wire, than you haven't properly sealed the wire, but even if you don't, I can't imagine any capillary seep would be much of an issue. If it is seeping through bearings, than you definitely aren't using the right bearings. Did you swap out your bearings for sealed ones? If so, do you know which ones?

I also don't see how FF would be easier to use. It would require complete disassembly of the motor in order to replace it, including scraping it out of every gap between the magnets, versus doing a simple flush with an oil, like with a rear differential. Hell, if you put threaded drain/fill hole on the motor, you wouldn't even need to remove it from the bike, just tilt it over, let it drain into a funnel/bucket. Rotate the wheel and fill it back up.

And did you include a pressure relief valve?

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Re: Make a watercooled high kw motor and I'll buy it !

Post by Ohbse » Feb 20 2017 1:32am

atarijedi wrote:If it is seeping along stranded wire, than you haven't properly sealed the wire, but even if you don't, I can't imagine any capillary seep would be much of an issue. If it is seeping through bearings, than you definitely aren't using the right bearings. Did you swap out your bearings for sealed ones? If so, do you know which ones?

I also don't see how FF would be easier to use. It would require complete disassembly of the motor in order to replace it, including scraping it out of every gap between the magnets, versus doing a simple flush with an oil, like with a rear differential. Hell, if you put threaded drain/fill hole on the motor, you wouldn't even need to remove it from the bike, just tilt it over, let it drain into a funnel/bucket. Rotate the wheel and fill it back up.

And did you include a pressure relief valve?
Yes, I had a breather in place. You simply cannot feasibly seal up wires, at least not without extraordinary difficulty - far, far in excess of any perceived difficulty on servicing. Real sealed bearings add substantially to no load torque, plus they seal stuff out of the bearing - not on the other side of an imperfect shaft.

I don't really care to convince you of anything, I'm simply stating that I have used both (for 10's of thousands of KM's for that matter) and FF is simply a much, much better solution. You're free to oil change your hub to your hearts content, I'll be very happy with my no mess, no mods required, highly effective and service free solution over here.

The forced air solution looks overly complex, is electrically inefficient, has added complexity (and breaking points), opens the motor for contamination, sounds unpleasant and costs substantially more than simply squirting 8ml of fluid into an existing hole in your motor cover (brake disc install is painless). Not to mention its effectiveness is unproven vs the guaranteed solution of solid state, silent and efficient FF + Hubsinks.

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Re: Make a watercooled high kw motor and I'll buy it !

Post by Offroader » Feb 20 2017 1:08pm

Someone should always try the FF first and if that isn't good enough then fill it with oil and compare the results. You can easily switch over to oil from FF if your results are not good enough.

I believe FF may have the advantage of covering the whole stator, while oil filled may only stay at the bottom.

I may switch over to FF, just going to wait for more reviews first. At some point I'll probably convert my MXUS turbo to FF and then can have a direct comparison of both. Especially after using my forced air cooling and knowing its limits.

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Re: Make a watercooled high kw motor and I'll buy it !

Post by Jestronix » Feb 20 2017 9:45pm

This all comes down to use case, punching up several klms of hill needs a shite load of heat sched, no matter the size of your hub it will over heat at some point. a nice big midrive is the answer but just as complex as a hub that is water cooled, in fact a mid drive has more failure points ?

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macribs   1 GW

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Re: Make a watercooled high kw motor and I'll buy it !

Post by macribs » Feb 20 2017 10:43pm

More failure points? Guess that depends on the choice of motor and what side you choose to run the chain. If you run mid drive crank setup with hi output motor surely the chain and sprockets will wear easily. A left side drive with proper chain and sprockets should be close to bullet proof. Now if you choose the right mid drive motor for your kind of riding already from the start and make sure the gear ratio matches your need you should be golden.

Water cooling when factory made like the DLC 28 mid drive, or some of the golden motors I would say not to worry about break down. Sure it adds another layer of complexity regarding running cooling hoses, radiator and a pump but even if a pump should break on a ride it will not mean you need to call a flat bed to get hauled back home. Limping home without making much heat in the motor will get you safely home. Todays pumps will easily run for several years without any problems. They are cheap too, so if you have doubts do a yearly swap.

I think that mid drive will present fewer problems after initial install and hook up then a hub motor that is running close to it's limit ie 100 degrees weather.

The easy to change gear ratio will make sure you can have easily swappable setups for various scenarios. Gear for max torque for heavy hill climbs or swap to different ratio for a week of touring paved roads for a "walkabout" if you know your cruise speed will be high.

Only challenge with mid drive I would say is initial setup, as there ain't much of ready made kits out there today for higher power mid drives that don't run crank. Also frames might need a little custom work, or at the least some custom brackets or clamps to secure the motor to frame or swing arm. When that is done just ride and be happy.

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Re: Make a watercooled high kw motor and I'll buy it !

Post by Jestronix » Feb 21 2017 12:14am

Yeh the 5kw watercooled golden motors look nice for a mid. couple that with one of those GAS sprocket setups as a direct drive and it could work well.

Im thinking of not using the crank and dropping the pedals making essentially a ultra light moto with a 5 to 10 kw range. I have also wondered about adapting a small gearbox off a dirt bike, like a 50cc gearbox, complex but could work?

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Re: Make a watercooled high kw motor and I'll buy it !

Post by macribs » Feb 21 2017 4:09am

Probably not what you wanna hear but here it goes. Gearbox or not have been the theme for various threads here at ES. Only a very few have actually had success with adding a gearbox. Or should I say moderate success? If they was to do it again I am not sure they would actually be using gearbox. Because gearbox is a band aide where people try to get an undersized motor to do climbs or loads that is not possible stock.

If you need a gear box in an electric bike you are doing it wrong, or more correct have chosen the wrong motor and or controller. Avoid the losses in the gearbox, the added complexity and the man hours to make a custom solution gearbox. If you look at gearbox threads here on ES, consensus is that money is better spend on buying larger motor then put into a gearbox.

Rather then looking at the 5kw motor that peaks at 10 kw, take a look at the 10 kw motor. Peaks at 20 kw. It comes in either fan/air cooled version or water cooled version. The 5 kw is about 400 $ and the 10 kw is 650$ from goldenmotor.com. You can use anywhere from 48-144 volt. You should be able to get so much power from the 10 kw version that you will never miss a gearbox. If you are a speed freak and aim for high top speed you could do higher voltage, or a controller with field weakening.

That 10kw should make for a nice and easy swing arm mount for a left side drive.

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Re: Make a watercooled high kw motor and I'll buy it !

Post by Jestronix » Feb 21 2017 10:04pm

macribs wrote:Probably not what you wanna hear but here it goes. Gearbox or not have been the theme for various threads here at ES. Only a very few have actually had success with adding a gearbox. Or should I say moderate success? If they was to do it again I am not sure they would actually be using gearbox. Because gearbox is a band aide where people try to get an undersized motor to do climbs or loads that is not possible stock.

If you need a gear box in an electric bike you are doing it wrong, or more correct have chosen the wrong motor and or controller. Avoid the losses in the gearbox, the added complexity and the man hours to make a custom solution gearbox. If you look at gearbox threads here on ES, consensus is that money is better spend on buying larger motor then put into a gearbox.

Rather then looking at the 5kw motor that peaks at 10 kw, take a look at the 10 kw motor. Peaks at 20 kw. It comes in either fan/air cooled version or water cooled version. The 5 kw is about 400 $ and the 10 kw is 650$ from goldenmotor.com. You can use anywhere from 48-144 volt. You should be able to get so much power from the 10 kw version that you will never miss a gearbox. If you are a speed freak and aim for high top speed you could do higher voltage, or a controller with field weakening.

That 10kw should make for a nice and easy swing arm mount for a left side drive.
So really a gearbox would only be of use in a low voltage low wind motor where you need the extra speed and climbing on a low wattage setup.

RPM is interesting here, on a gasser youd be looking at 8 to 10k ? matted with a 5 speed gbox. so 6k rpm is max on single speed ?

If so id need to know that when im hill climbing that im not sitting the motor down to low in RPM to avoid heat stress and inefficiency yeh ?

as electric motors have full torque in reality id need to pick a gear that is halfway between climbing and a nice 60kmh top speed. All within 6k rpm. mmm

I guess zero and such are using single gear yeah ?

Man hours would be huge to fit a gbox, but does it still have value in the 6000rpm limit.



Long working life (>20,000 hours)
Low noise, high torque
Excellent performance characteristics
High efficiency (>90%)
High reliability
Rated voltage : 24-120 VDC
Rated power : 200W-20,000W
Rated speed: 2000-6000 rpm
Cooling Options: Fan or Liquid
Temperature Sensor Installed: KTY84-130 (.PDF)
Stepless speed control, dual-direction

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macribs   1 GW

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Re: Make a watercooled high kw motor and I'll buy it !

Post by macribs » Feb 22 2017 1:15pm

Not sure I got what you are asking in that last post. With a mid motor there are a few ways to impact the ratio. As with BB hubs your wheels matters.
Then there is single reduction, or direct drive from motor to rear wheel. Where the sprockets take care of the ratio. If more reduction is needed a one stage could be used, like a jack shaft from the motor - introducing one more step of reduction.

If you aim for a top speed of 60 Km/h you should get a torque strong enough to climb vertical. Insane acceleration and climb power. Even if your top speed should be 60 MPH you should still be able to to climb anything. There is a calculator for simulating various gearing ratios. You can take a look at that and see various outcomes.

Yes, Alta, Zero, Energia, Victory etc are all without a gearbox. And they have great acceleration, yet good top speed. The only commercial electric motorcycle I can think of that is using gearbox is the Lita Sora, which uses a CVT gearbox. Alta has recently done very well with their electric dirt bike, no gearbox, and did well on one of the great Red Bull events, the Straight Rhythm, Videos on the tube.

Also look up some of the builds by Matt (Recumpence).
Matt uses various numbers of the super light yet powerful Astro 32xx motors. He uses the Davinci drive as a jackshaft with slipper clutch and have done builds close to or more then 30 kw peak. Even when those Astro motors spins with top RPM at 10.000+ there is no need for a gearbox. He did a trike build with a dual or triple Astro 3220 that hit 86 Mph. With unbelievable torque and even good mid range torque and acceleration.

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Re: Make a watercooled high kw motor and I'll buy it !

Post by Offroader » Feb 22 2017 3:03pm

The deal with Mid-drive is that I think they still are a few years away. I personally don't like the fact that I can't use a Max-E controller with them, I really love the features of the Max-e, including the easy charging, sin wave silent operation, plus many other features.

I don't like the idea of losing regenerative braking with a mid-drive, but I could probably live with that for the better handling.

The drive trains for the mid drive kind of suck. I heard you can't really do wheelies easy with mid-drive because of a delay in the drive trains.

Basically, mid-drives need a few years to get perfected, they are getting improved quickly now as many people are working on them, but they just aren't there yet.

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Re: Make a watercooled high kw motor and I'll buy it !

Post by macribs » Feb 22 2017 4:45pm

Offroader wrote:The deal with Mid-drive is that I think they still are a few years away. I personally don't like the fact that I can't use a Max-E controller with them, I really love the features of the Max-e, including the easy charging, sin wave silent operation, plus many other features.

I don't like the idea of losing regenerative braking with a mid-drive, but I could probably live with that for the better handling.

The drive trains for the mid drive kind of suck. I heard you can't really do wheelies easy with mid-drive because of a delay in the drive trains.

Basically, mid-drives need a few years to get perfected, they are getting improved quickly now as many people are working on them, but they just aren't there yet.

I think the time is just right for mid drives. Even hi powered ones. With regen, stable drive and wheelie capabilities. And certainly you can use your Adaptto if you so like for some mid motors. Its about max rpm and pole counts.

Some mid drive motors are able to use Max-E controller. Iirc the max E-Rpm of Max-E is around 70.000.
ES wiki wrote:ERPM = Electrical RPM or eRPM is calculated by multiplying the number of pole pairs by the actual RPM:

eRPM = pole pairs * RPM
It can be a limiting factor in controller selection for high RPM and/or pole count motors (usually RC-derived designs). using the [Golden Motor HPM-10KW] as an example:

eRPM = 4 x 6000 = 48.000
To be honest today I think if you aim for >10 kw for a mid drive it will come at a cost. Either cost, weight, noise or a combination of this. Sure you can go with Astro 3220, probably the lightest and most powerful motor around, supposedly does 12-14 kw peak (few sec only but then again in a few sec u r @top speed). But Astro ain't silent. Also you are pretty much locked to one specific ESC to get the most out of that motor, like Matt has done. Then you need reduction as motor runs at 10.000 Rpm. If you are ok with the sound from Astro a 3220 or multiple 3220's will give insane power to weight ratio. You could go Davinci drive or tangentdrive if you like something ready made. Expect costs to be from 900-2xxx $ for a complete driveunit with reduction and motor.

There are others too, like the Joby motors. Joby motors are very powerful yet lightweight. One ES member is pushing 20 kw or slightly more on a Joby build. Can't remember who. Those Joby motors is about 1200-2500 $ iirc. And you can your Joby custom build to your needs.

So lets look at the Golden Motor HPM-10KW. This 20 kw peak motor has 8 poles, so should mean 4 pole pairs.
So even run at max rpm @6.000 the e-rpm = 48.000. That means you could use Max-E controller should you so wish. Using stock firmware however you will top out @ 14 kw or so iirc. Sad really for a motor that can do 20 kw. So for this motor either use a more powerful controller or consider using unlocked firmware with adaptto get closer to the 20 kw peak. The Golden motor is about 600 $. Seems like a great buy. And as a lefty you will have regen as well. This motor can be either air or water cooled.

Don't forget the DLC 28. > 30 kw peak output. 17 kilos. But hey. Weight is centralized. There is or should be soon a DLC 28 clone, improved and even more capable. Peaks at >40 kw. 1300 $ iirc. That clone motor might very well be one of the hottest thing around for the 2017. It will give you dirt bike power.

If you got a left side drive that is not connected to your crank and pedals I can't see any reason as to not use regen. Left side drive should give you regen right out of the box, permitted the controller you use allows regen. Rc ESC usually don't allow regen, most ebike controllers do.

About the wheelie, bzwhindtalker does wheelie all the time on his LMX bikes. Several BHT builds have shown great wheelies. Astro builds done wheelies. Even the right side tangendrive with Astro 32xx does wheelie. You could be right for some builds when it comes to builds that run their mid power via crank and stock bike chain/sprockets. But if you look hard I would be surprised if there ain't no one doing wheelie with BBSHD, BigBlocks, Bafangs, Cyclones etc.

The only down side I see for mid drives is the lack of ready made frame kits for mid drive. If there was a Vector, Qulibix, NYX etc frame kit purpose build for mid drives I think we would see a real growing number of hi powered mid drives. The next step for frame designers will have to be to step up and make frames for mid drives, tbh I am kind of surprised we haven't really seen those around already.
Last edited by macribs on Mar 02 2017 7:08pm, edited 2 times in total.

Jestronix   10 kW

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Re: Make a watercooled high kw motor and I'll buy it !

Post by Jestronix » Feb 22 2017 11:49pm


The only down side I see for mid drives is the lack of ready made frame kits for mid drive. If there was a Vector, Qulibix, NYX etc frame kit purpose build for mid drives I think we would see a real growing number of hi powered mid drives.

Dead on ! when this happens there will be an explosion in high power mids, belt drives are up to this ?

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Re: Make a watercooled high kw motor and I'll buy it !

Post by macribs » Feb 23 2017 12:19am

Yeah I think belts can take upwards of 100 kw no problem. Then there are reinforced carbon belts. Probably take twice that.
Then again, cheaper and more easy way would be to use mc/mx chain and sprockets. Cheap and reliable, especially the O-ring chains.

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Re: Make a watercooled high kw motor and I'll buy it !

Post by Jestronix » Feb 23 2017 12:38am

macribs wrote:Yeah I think belts can take upwards of 100 kw no problem. Then there are reinforced carbon belts. Probably take twice that.
Then again, cheaper and more easy way would be to use mc/mx chain and sprockets. Cheap and reliable, especially the O-ring chains.
Its the silence i search for. why i love my dd hub and sinewave controller.

100kw man ! but at a reasonable width for a bike install may a lot less.

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Re: Make a watercooled high kw motor and I'll buy it !

Post by macribs » Apr 29 2017 1:00pm

Have a look at the two TP 100 and TP100xl.
The first one 25kw, the second 72kw and only weighs 8 kilos. Smaller one got 25.000 RPM max. The larger 12K RPM. Edit:Forgot the link.
https://endless-sphere.com/forums/viewt ... 30&t=87917

Never heard of this company before, and google didn't find much. I don't know if the people behind TP is flat out mentally ill or if they are mentally above the rest of us. Heck even at half the peak power it would still be amazing. BS marketing lies or would something like this even be possible?

Inrunner so you can easily add water jacket but I guess a fan would work better.

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