Yeah it did seem rather personal, didnt it 
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FWIW i think these are pretty cool, it would seem that a lot of work has gone into them.
I would really love to see some proper data on their cooling effect, perhaps some testing could be done on the skp dyno 
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Data on the bench can be organized …
Here is some wheels on the ground Metr data. Rough pavement hilly terrain. Two different routes trying to keep the same speeds.
Without HXHD
With HXHD
Without HXHD
With HXHD
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To establish a baseline temperature difference between the motors, start with a run without the HXHD installed. Mid-ride, install the HXHD on one motor and continue. In the logs, separate the graph lines to display individual component stats like the temperature of each motor.
Tap this to open a window displaying all parameters.
Tap a parameter to hide it from the graph. Tap the arrow to split the graph and display each recorded side separately.
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Thats almost what i did. The time stamps show one hour of cooling between each run, and the temps are actually warmer when starting with HXHD in both cases.
One motor on, one off is not the right way because my temps often vary between motors. I ride heavy on the toe side so that motor works harder is always warmer.
Without HXHD
About an hour of cooling, warmer start temps lower average and lower max.
With HXHD
Without HXHD
Again over an hour of cooling, motor start temp is always warmer. Average and max is lower.
With HXHD
They function or i would not sell them. I will also offer discount if others want to do this kind of testing.
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HXHD bench test with 6485 Reacher motors.
HXHD bench test with Flipsky 6384 motors
Can you redo the test but take temperature measurements via the built-in temperature sensors in the motor? They are located in the stator which is the more temperature critical area of the motor.
The temperature of the surface of the motor can doesn’t give me much info about how long it’ll take to hit thermal throttling which is based on the temperature of the stator not the can.
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Here is clip #1 from the video for sealed can flipsky motors. You can see i have vesc tool open and show the internal temperatures of each motor.
Here is clip # 2 from the video for open can Reacher motors. You can see i have vesc tool open and show the internal temperatures of each motor.
The HXHD cooling fins are not installed for Reacher motor test but it still provides a significant improvement on the internal temperatures of the motors, especially when the motors are not spinning.
The external temps are just as important as internal temp, especially when proving something that can be easily tweaked to read inaccurate temps.
Thermal throttling is a safety feature. Motors will lose efficiency - consuming more amps and losing torque anywhere above their optimum performance temperature which is between 20° and 40°c
I was not aware. What should I be looking out for ? I’ve only ever monitored via vesc tool
Edit: just watched the videos.
I think a great proof of concept for these would be to go for a long ride on a 2wd board. One motor with the coolers and one without. Then we can graph the vesc log of each and compare.
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Heat! If the can is saturated where does the stator’s heat go? A hot stator makes winding resistance increase so the esc will push more amps in that swirl into more heat because magnets wont resist the same when they get hot… its a rabbit hole if you want to look at all the factors but here is a quick read up
Basically, if its hot on the outside its definetly hot on the inside. And vis versa. Thats why we have that thermal throttling limit. Otherwise we would keep jamming more amps in until the esc or motors or battery cant handle it and fail.
Its a proven concept across all electric motors - heat dissipation is not a new concept. Electric motor heatsinks existed long before i did.
The design challenge was that external rotor motors rotate. So making something that dissipates the heat effectively while being safe, easy to install across multiple brands and sizes, compact and cool looking took some effort. My first functional prototype was in the summer of 2021.
Although it looks like its an invention, really its just an adaptation for the external rotor motor.
If I understand correctly, you’re extracting heat from the stator through an air gap and then through the can?
Yes thats the heat being extracted. The thermistors inside the motors with HXHD read ~ 10°C less than the motors without the HXHD installed, as shown in the videos. Also the external temp is lower, as the heat from the stator is the same heat that goes to the can of the motor.