A simple heatsink for a mxus 3000

[Jestronix]

Hi guys , I had some aluminium channel lying around and some heatsink tape, so thought I'd add some heat sinks to the beast.

Ran the hub at 100kmh and they stay well intact. Pushed 8kw through it, got home and those fins sure heat up, so they are dissipating heat. I noticed a slightly better cool down period. I'll be doing the sides at some point.

 

[cwah]

Would be good if difference is signficant

 

[Jestronix]

Heatsinks shed heat, should be a significant difference when it's complete, I'm using ATF and will be at some stage using external water cooling. A good mist over heatsinks in cool air should work a treat, hopefully a litre or two can double my ride time

 

[parabellum]

Tape and paint is probably the killer here. Thermal epoxy on bare aluminum would multiply the effect. Desperately waiting for data.

 

[Jestronix]

Why they don't help us out from the factory I don't know. Cost , but I'll pay $50 more to have a motor decked out for cooling.. Justin's test tunnel is needed on this one.

Yeh the epoxy stuff is the go, and sanding would be too hard, maybe stage 2 eh

 

[Jestronix]

I ran a cable tie around the heat sinks today to pull them against the hub, wow,what a difference ! Obviously they are now making better contact under pressure and picking up more heat.

I went for an 10 Klm ride and pushed about 8kw, I didn't have to back off due to heat this time and I was out at a hot time of day too, without proper tests it's all by perception but I definitely was able to ride longer.

What would rock would be mounting some heat tubes around the hub and have the fins mounted in the spokes, non invasive and could return some interesting results.

 

[macribs]

Very cool mod. Would love to see some data how good your heat sinks works.

 

[Jestronix]

After a fair bit of riding in the 8-10 kW range I'm finding temp with oil and the heat sinks is making a good difference, but no amount of heat sinks or air blowing over a hub is going to remove these types of kW, nor any sustained hill climbing. It helps and allows me to cool down quicker after so thrashing, easing back to 500w to 1000w for a minute or two and I can push the power a bit more. Active water cooling is the only answer I can see for big kW. I'm seriously looking at moving to water cooling, but the nightmare over opening the axel and making things fit

The other option I'm thinking about is hubs front and back with 4kw each, two controllers 40amp 120v , so near 10kw bursts, biggest problem I have now is the front lifting, that 8kg on the front wheel could help, but will bring agility into question.

10kw is really where off road peaks for an ebike , unless u go stealth style frame. Also spinning tubes and ripping valves becomes an issue, also pulling up from 70kmh on a dirt track is interesting or almost flipping on wot. I can say though as u go higher than 8kw the acceleration difference is not worth the extra kW, 10kw and 8 kW are so close that really I suspect I'm just adding heat aboVe this. Two hubs has many advantages which I'm ultimately thinking is the answer to 10kw +

 

[macribs]

If that new controller exposed here the other day will come to market I think such a controller paired with the Revolt 160 will have a potential for high power setup.
Get the weight of the motor in the frame, and let the motor unleash 20 kw + in peak power. Should make for an interesting e-bike, without the penalty from the heavy hub motors in rims.

 

[macribs]

This is the kind of thing I have been looking for, I am surprised more people have not tried it. Simple, cheap, non-invasive.

Other than a small amount of aerodynamic drag, I cannot see any of the downsides that most other methods involve. Comparing effectiveness to other methods should be done, however effectiveness compared to nothing at all should be considered.

I think a series of vertical cuts in each upright of the "U" channel, would give more surface area and allow more airflow to the heatsink. This is what PC heatsinks always look like, very little flat un-interrupted surface area.

You mean more in line with what Madin88 has done?

thanks for the further tests.
when using statorade and drilling additionally holes to the covers, it will improve things by another 50-100% (hopefully i'm right this time with the numbers :lol: ), but how would it look after some miles in real world with dust and small debris inside the motor gum up with the FF?
IMO this is something you do not want to have so either statorade or drilling, but not both.

look what i have done with a MXUS 45H rotor:

i turned off almost 1kg of material and increased the surface area. the back iron now is about 2,5-3mm thick at the bottom of the fins. the fins are about 3mm deep. since a paper clip does not show magnetism on the outer surface, the thickness should be sufficient.
with custom made sidecovers with integrated spoke flange (similar to the prototype of Justins Grin Tech motor, or Bionx), i believe the MXUS 3000 could be turned into a 7kg motor making hub drive MUCH more attractive 8)

 

[spinningmagnets]

One kg is 2.2 lbs, so...roughly a 2-pound reduction. Nice

 

[hydro-one]

Hi , interesting ! why not get a bigger motor and forget about heat problems,,,,50mm stator hubmotor 17" moped wheel is the minimum i would reccomend to the high performance crowd

i like what is done with the heat sinks carved into the backiron.. these would help to cool the magnets (least thermally stable component?) , side covers would be my target if you wanted to do fancy "air conditioner" type blades. with oil cooling and epoxy impregnated windings of course...

 

[madin88]

Hi , interesting ! why not get a bigger motor and forget about heat problems,,,,50mm stator hubmotor 17" moped wheel is the minimum i would reccomend to the high performance crowd

i like what is done with the heat sinks carved into the backiron.. these would help to cool the magnets (least thermally stable component?) , side covers would be my target if you wanted to do fancy "air conditioner" type blades. with oil cooling and epoxy impregnated windings of course...

have you ever heard about the disadvantages of a heavy hub or unsprung mass in general?
motors with 50mm stator have about 12-13kg these days. such motor might still feel comfortable when used on a >100kg scooter or motorcycle, but if you have such heavy beast in the rear of your lightweight ebike, the handling will suffer alot (mainly offroad or on uneven street its very noticeable)

 

[madin88]

Madin's mod is quite impressive, eh? That is from Justin's definitive cooling thread in case anyone missed it. https://endless-sphere.com/forums/viewtopic.php?f=2&t=48753&start=1125.
It should allow for roughly a 300% improvement in surface area.

with the triangle shape fins, the surface area between the spoke flange is about 80-100% larger, but the best thing the motor now has 1kg lower weight^^

 

[Jestronix]

Today was my big test, about 2klms and 300m climb, with a 26" wheel. With super large tyres so a allmost a 27" wheel. Not the best for climbing hills but nice to ride off road. I managed to climb non stop and reached 100c briefly, what I have noticed is rapid cool down time, I think my next move will be some arctic silver thermal grease, sand back to metal and cut grooves in the u channel. One thing is that the thermal tape I'm using allows for good contact area against the arc of the wheel, grease may be ok at the right thickness.

Would be great to see Justin test this with FF, pulling heat right off the magnets is a great spot as the ATF or FF is not only pushing best to the side covers but up to the magnets, the magnets having heat sinks helps the transfer again.

A motor in the frame requires some beefy chain and most to work , beyond my enthusiasm levels but two wheel Drive is not out of the question. My worry is front suspension carrying the weight, specially on rebound.

17" wheel is another good solution, but I can barely keep the front when down as it is. Really this is where a good flux or Nyx comes in, long travel arms.

 

[macribs]

You don't need similar motors, up front you could have a light weight geared motor for instance. Just give front motor its own controller and throttle. Running a geared motor in front wheel really should give you easier climbs, better accelerations and the capability to run higher loads, ie on a cargo bike.

 

[Jestronix]

What's a good geared motor that will handle 5kw ? And remove heat well?

 

[amberwolf]

Geared? none I've ever seen for ebikes, unless you modify it for that kind of power.

 

[madin88]

What's a good geared motor that will handle 5kw ? And remove heat well?

maybe the "double wide mac" come close to that:

https://endless-sphere.com/forums/viewtopic.php?f=25&t=68784&start=50#p1098795

but it's not available yet..

 

[macribs]

What's a good geared motor that will handle 5kw ? And remove heat well?

maybe the "double wide mac" come close to that:

https://endless-sphere.com/forums/viewtopic.php?f=25&t=68784&start=50#p1098795

but it's not available yet..

Theoretically one should be able to get twice the power of 1 mac motor if two are run as double wide. Enertec (?) has a motor that comes in standard and double wide. Can't see why it should not for twin mac's?

 

[madin88]

a double wide motor should more lead to 3-times the power than twice, but it also depends on how well it can give off the heat..

 

[Jestronix]

if a motor carries more mass, its not giving off more heat , its just able to absorb more peaks before it reaches over temp right? lugging around extra metal for the ability to soak up a few big peaks is a little counter productive, wheres the heatsinks ? the first motor company to come up with cooling and big power in mind will be on a winner. Surely its only a matter of time till mxus etc comes out with a factory water cooled unit or very least heatsinks etc. My dream is double wide mxus water cooled make it and ill buy it, even its its $1000 people are paying 10k for ebikes, $1000 motor isnt a deal breaker.

 

[macribs]

if a motor carries more mass, its not giving off more heat , its just able to absorb more peaks before it reaches over temp right? lugging around extra metal for the ability to soak up a few big peaks is a little counter productive, wheres the heatsinks ? the first motor company to come up with cooling and big power in mind will be on a winner. Surely its only a matter of time till mxus etc comes out with a factory water cooled unit or very least heatsinks etc. My dream is double wide mxus water cooled make it and ill buy it, even its its $1000 people are paying 10k for ebikes, $1000 motor isnt a deal breaker.

For Electric scooter/motorcycle motor
We produce 10"/12" 205 motor from 1000W~3000W, and 13"~17“ 273 motor from 3000W~8000W.
Our greatest motor is Qs 8000W 273 (50mm magnet height) hub motor extra/V3 type
http://tzquanshun.en.alibaba.com/product/60082173269-800325938/13_8000W_273_50H_Extra_type_V3_Electric_Scooter_Hub_Motor.html
8840W continuous, 11245W peak @ 72V 200A, which might also call it 10kW.
N.W. 23~24kg, maximum 800~1500RPM, 200-300N.m.
For 8kW V3 motor, we suggest peak 150-200A battery current for general usage (72V). It's most stable configuration & longest life time.
Some EV enthusiast adjust it to be 350A, the output power is far more than 8kW (maybe 17-19kW).

We strongly suggest to install Thermic Probe (KTY 83/122), so that controller will turn off when it's 120°C inside of motor.

Also. another costomer make it 96V battery, 400A peak phase current, 19kW output.
We call it overvoltage usage, the life time might be shorter.

 

[Jestronix]

Now u are talking . Now to work out if the 273 spoke will fit in a flux frame

 

[macribs]

The 273 comes with optional water cooling as well, ready made from manufacturer. Push as much amps as you can and ride as hard as possible and let it all cool down by a large radiator. The bike spoke version has 152 mm drop outs. 10mm axle flats.



The 205 50h qs motor I've heard people talk about 15 kw peak power. I wonder what the 273 motor can peak for a few seconds? And what about 10 seconds? Better get phase wires like garden hoses, cause I'll bet you that 273 will suck down hi amps like a southern girl @ happy hour

I'll see they recommend 530A phase current.......

The motor I ordered arrived well packaged and spinning it by hand Im impressed with how slowly it spins down for its massive size.

Thank you Vito. Im looking forward to pumping a lot of amps into it.

Hello Luke,

With my pleasure, I am so glad the motor arrived well packaged.
And I am also looking forward to hearing latest news about QS 273 40H Motor.
Please note the Winding: 65X3T-, 48V 807RPM, 16.8kV.
The copper wire cross section is 13.26mm2, we suggest to set 530.4A peak phase current (40X13.3).
Attached similar test report /performance curve "QS 13 72V 4000W 1217RPM V3 Test.pdf" for reference.

If any question, please feel free to contact with us.

Best Regards