Why would the same motors/setup spike consistently in all logs except the ones with added statorade? I tested the statorade and it is clearly non-conductive, do you think this means the statorade may be acting as shielding?
I actually not sure, but in the first log you can see that this mini temp spikes occurred the moment you accelerate and after disappear or even swing down below the temp it was before. I wouldn’t read this as real temp rising of the motor.
Maybe in the second ride your motor wires where laying a bit different from the first ride or you didn’t accelerate that hard like first ride due to lower battery voltage etc. Maybe it has to do with the cooling liquid. Just wanted to mention it so that you take it into account.
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Okay lol, I am going to suggest people not do this. My testing will be on hold until I get a new set of motors to inject the rest of the statorade in. I was taking it slow at first but after about 60C one of the motors smoked up pretty bad and temps jumped over the next 20 seconds to well above 90C and now that motor just rattles. 
If anyone else does this, do small amounts of current sustained over a much longer period of time… take it slow lol!!!
From the feel of it, the cans are noticably hotter now than they were after applying the thermal paste. In stock configuration, both the cans and hangar would heat up slowly over time about evenly. With thermal paste, the hangar would heat up quite a bit with the cans still cool. With statorade + thermal paste, now the cans heat up as fast as, and with just as much heat, as the hangars… so its clearly doing something.
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Damn, this probably mean that the temperature sensor doesn’t have good contact with the windings, in my motors with the sensor glued to copper with a bit of thermal paste it gets instantly the temperature rise
Post some pictures if you open it up please
@torqueboards this probably also explain why they cooked on pneumatics, they heat faster than the heat is transferred to the sensor
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what is needed is big fat windings (more copper) to lower the resistance… twice the copper with the same # turns (half the resistance) gives half the heat for the same acceleration… eliminate the heat at the source rather than attempting cooling after the fact
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I have burnt out one of my motors from the discharging exercise, so I decided to give a single motor a go with the statorade. I rode super light today, only having one motor, but I still got some useful data from the run to compare to previous trips.
There is a huge difference with time it takes to cool down the motors. Pics included for comparison sake, similar motor usage during cooling for the 82-72°C readings, and a bit less of a direct comparison for the 82-62°C so take it with a grain of salt.
No statorade:
- 82°C --> 72°C = 1:40
- 82°C --> 62°C = 4:50
With statorade
- 82°C --> 72°C = 0:46
- 82°C --> 62°C = 2:08
Keep in mind, I did have the second motor removed for the statorade run this time, but the bare axle was wrapped in neoprene so it wouldn’t be cooling that much extra… I am curious to see if these temp drops are consistent after adding on the second motor again.
I do keep noticing the cans getting significantly warmer now though which is a super promising sign- before, with thermal paste between the axles and motors, the hangar would be burning up compared to the cans, and now with paste and statorade both heat up just as much to the touch, if not the cans maybe even a bit more… I’m loving it.
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This is really good, I think the future lies in completely sealed motors and Statorade for a long life, need quite a lot of re design to make them truly sealed
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That’s a huge difference in cooling time 
Way to go for science! lol
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There is something I was wondering about this. The Statorade spreads the heat from the core to the can, which has more surface area, BUT
The magnets are on the can… Which for NdFeB type magnets (which is what most motors are), starts losing magnetism permanently at over 80-100C, but yet, quality magnet wire insulation can resist temps up to 180C or more. Which means the stator can handle a lot more heat before damage than the magnets on the can could. So by using Statorade to spread the heat all around, theoretically the motor has less overall performance potential? than a system where the core itself is cooled independently, or even forcing air through the motor?
This is not a statement I’m actually curious what the potential is here. I.e. if one was to drive a motor to compete thermal failure, would the sealed statorade motor fail first vs a motor that has a cooling circuit in the stator or fully vented with fan blades on the can? (imagine the raptor motors but actually thought through, i.e. copper channels through the stator, a heat pipe of proper size that dumps the heat to a full size heatsink instead of aluminum trucks)
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On the contrary, the cooler you keep the motors the more efficient they are
On our motors most of the losses are due to the winding resistance, and copper increases the resistance following around 0.4%/°C, so if instead o maintaining the motor at 80°C, we allow it to operate at 180°C, we have a 39% resistance increase, so 39% more loses
One test that would be great if you did is to use a IR thermometer and see how hot the outside of the motors are getting, but if the sensor is reporting 80°C, they will be a lot lower
@torqueboards had said a long while ago that the magnets they use are rated to 140°, or something close, I would worry more about the glue holding the magnets
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Well the irony is, typically the higher temperature the magnets can stand, the lower their magnetic strength is, which is also a loss of efficiency. I do agree hot motors don’t move well, but is moving the heat to the magnets a good move? or is it better to pull the heat via high air flow or through the core of the stator instead?
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Got any high-res pic of this? Very interested
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For our use ( and ebikes and other uses that the motor is subject to the elements) I think moving the heat to the magnets is the best, else you will just fill your motor with junk
Water cooling would be cool (pun intended), but customs motors are needed for that
My view is that if the amount of heat your are producing are making the motor overheat, the problems is not the cooling, every bit you cool is wasted energy and loss of energy
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Well. Which direct drive motor is stock off the shelf? Aren’t they all custom to an extent? And there is a fair share of stock water cooled motors (maytech has a few).
But the heat thing, there is a balance of size too. You can’t just keep sizing up motors until it runs nice and cool, because then you’re going to have to figure out how to strap two 50lb pumpkins to your 20lb board. Even high performance electric cars run water cooling.
Even at extreme efficiencies, you have to deal with heat with power. 95% efficient motor, pushing 5000 watts, is producing 250 watts of heat. Quite significant. And 95% is in unrealistic territory.
I felt like Enertion’s copper heat pipe was onto something. Except they stuck the heat pipe in a steel drilled hole. Had the stator have copper inserts that extends to the axle making contact with the heat pipe, then giving an actual mass and fins for the heat pipe to dump into, it would’ve been way more successful imo.
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I agree, the thing to look as you said is efficiency, if you are running in a low efficiency zone, cooling will work, but there are other things that you can change
One nice way to cool it would be tiny holes in the stator core itself, even a small amount of water can do wonders to move heat away
But is comes as a problem for me due to you have to mound radiators, pumps and all that
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I think the problem is that, no matter what you do, 1:1 drives will be less efficient than geared. Hence why no electric vehicle other than PEVs run 1:1 drive. All hub motors etc have way underrated continuous power ratings due to heat. Improving efficiency is easiest by spinning the motor faster and reducing gear ratio, which makes it a moot point. So alternative would be ways to remove heat faster, I think water cooling is just too much with the extra parts, but air cool, copper mass and heat pipes may be worth looking at.
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Yeah, you have to spin up the motor to the point where the core loses start to get significant
The thing is, there are other ways to make the core loses go up and bring the windings loses down, and that is what I’m playing with in my motor
The hardest part is to find the load profile for a given vehicle and optimize for that
This why I need logs to find it
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Transverse flux motor design seems the easiest way to get the most copper in.
A cooling system seems to me a lot of complexity and risk of breaking down. The hanger could be used as a great heatsink if only can get the heat there. I plan to press the end of the stator into the motor case wall with a thermal pad between. Copper to thermal pad to mild steel. Looking forward to see how it goes
How did it go when it burnt out @Skatardude10 ? In my experience a burnt out motor throws u.
Using 270c rated wire (new thing out there) and lrk winding to further isolate phases to avoid cross phase short
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It didn’t throw me, I was holding the wheels locked at 0mph against the wall and pumping the throttle. I probably should have let the wheels spin a bit.
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except if they put that same copper in the windings i doubt they’d need the heat pipe so i’m not convinced
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