cool thanks for the quick reply
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I got a bottle of statorade on the way, I’ll let you guys know how it goes. As it is, thermal paste between the hangar and motors are working really well to dissipate quite a bit of heat to the hangar, with not so much to the cans… but over time the heat still rises to top out at the 85°C cutoff eventually, just not nearly as fast. I’d like to eliminate hitting the limit no matter how many amps, and if 30-40% better cooling is possible that would be super nice!
By the numbers, the statorade should be effective up to about 20 mph, which is perfect for cruising between spurts of speed.
Now my question is, has anyone here taken apart their TB DDs to get to the magnets yet? any advice for the best way to go about it? I hear the big bearing is really tough to remove.
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Looking forward to this, if you have time, try increasing the amount of statorade gradually, testing in the same route if possible, a long hill would be perfect, and also taking note at the no load motor current, should provide a nice graph that show how much you should fill the motors
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I’d do that but really I don’t think I have that kind of time to disassemble and reassemble if it’s a pain in the butt.
Although if it’s easy enough though, I may do a few quick additions, 1ml each time or something and compare logs. Maybe I’ll start with a certain route/speed with hard braking and accelerating at pre-defined spots, starting out with no statorade and letting the motors cool to the same temp each run while recharging. Hopefully I’m able to get a needle tip into the motor magnets somewhere easily.
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You could drill a small hole at the front of the motor, thread it and use a screw with loctite, no need to disassemble it every time
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Even easier… where the phase wires go in to the motors, there is silicone stuff that is really easy to poke through! The statorade needle injector goes right in quite deep. I was worried about the sensor board, so I double checked and the statorade is non-conductive.
I set a max speed of 20mph, and at full throttle measured no-load current on the first motor to be 0.4-0.5A, flip flopping, and the second motor to be 0.5A consistently. After 1mL of statorade, I saw no changes in no load current. At 2mL, the first motor is at 0.5-0.6A on one motor and 0.6A consistent on the other. After spinning the motors for a while, I noticed the current has dropped a bit… so I may try adding another 0.5mL to each side at some point after testing on the road for a bit.
It’s late and I have to work in the morning so I won’t be testing tonight.
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Haha nice! 
yeah the only other good location would be removing the front bearing but that’s going to be a pita to realign without a jig and press.
So that location is actually a good idea. You can always re-add the silicone.
If it works well we can add a threaded port hole that we can cover with just a bolt on the front of the motor.
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Ah I took them out and did constant hard acceleration and hard braking. The motors still increased to 65°C, still 20°C short of throttling, but I didn’t go too far because it was freezing outside and I hadn’t charged and only had like 30% battery left. By the end I couldn’t really push the battery amps I wanted to to keep going. It’s been rainy since then.
The statorade did noticably smooth out the temperature curves. I usually ride with consistent periods of coasting to allow motors to cool, and this latest test I didn’t replicate my normal riding style so it’s difficult to compare directly. Take a look for yourself though… tonight I want to export the data to Excel and compare total motor temperature over time vs total motor amps to get a better 1 to 1 comparison and to setup a formula that works to plot more data in when I get more testing in. I tried to find the most comparable record energy and distance wise. I’ve noticed ambient temperature doesn’t make a huge difference unless it’s mid summer TX, since my motors would still throttle by the end of my rides in freezing temps out here stock.
Normal motors with thermal paste between motors and hangars, 58.6 Wh in 1.81 miles:
with 2ml statorade per motor and same thermal paste between hangars and motors, and 75wh over 1.9 miles, with visually more constant acceleration/braking.
The motor temp line is at least a significantly smoother without little mini spikes up and down, I’m guessing some of the statorade is stabilizing the temp sensors readings a bit, and I’m thinking this doesn’t matter or affect performance good or bad.
Looking at ambient temps, the ESC min, since I’m using a heatsink… between the two logs there is a 5°C delta, and only 3°C Delta for the average ESC temp- so I’d give the non statorade run a minimum of 3°C handicap when reading the motors. With almost 9A higher Avg motor amps and 8A higher battery over longer distance on the statorade run, statorade motors are running 1°F cooler by the end vs no statorade, but taking into account the ambient temp handicap, it’s not yet a clear a win on this limited test. Maybe the difference will be much more clear in the temp throttling range: the info sheets talk about running max 75C with statorade vs 100C without on ebike hubs and I’ve yet to test to throttling territory.
Again, at this point the difference is not yet super clear. I am considering adding in another 0.5ml per motor soon, but I’d like to get a much longer test run in on a full charge and push the motors to throttling and then compare again with another similar set of logs at throttling temps.
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That seems promising
I thought of another easier (maybe) way for you to test the ideal amount
Use FOC openloop on the terminal with a high current until the motor reaches maximum temperature, them just go full throttle on the bench and graph the temperature drop while the motor goes full speed
You should be able to see a point where the temperature starts dropping more quickly, that would mean that even subject to the high centripetal force there still enough fluid to bridge the gap
Keep in mind that this amount may be too much and cause drag at lower speeds
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I gave this a try, this was my initial go-totest but it seems acknaniacs firmware has some trouble running FOC openloop. I was able to get the control buttons in the tool working by changing the APP mode to not include PPM, but still the FOC openloop commands would just cause a single quick spike in current and then nothing. Not sure what’s up with the command on Acks fw. I’d go back to the newest VESC tool but I hate breaking compatibility with METR, it acts super wonky on my setup with all the same settings, feature bloated, flashing takes forever, don’t like the ride feel.
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For future DD iterations, that would be a wonderdul addition Dex!
Only concern I have in general about this stuff is that they say this stuff lasts a really really long time, but I wonder what would need to be done if it would ever need to be flushed, cleaned and re-added.
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I’m very interested!
I have some Carvon V4s I’m re-purposing, very interested in the thermal (paste) you’re using… these drives have 1,500miles on them and the bimetallic corrosion internally is evident… If I can find a low viscosity thermal paste to use vs. using just some anti-seize would be excellent…
When Jerry built these drives he seems to have swam upstream vs. common bi-metallic construction and opted for ease of machining the pieces…
may I ask what (type, brand, viscosity) of thermal paste/grease you’re using on the stator/axle interface? Statorade looks promising but the Carvons are open can… I’ll try it later on the elofty variant I have…
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You could just lock the motor and accelerate
Put the nose of the board agains a wall, get on top of it and let it cook
I did it sometimes to discharge the battery
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My drives were relatively loose on the hangars- as in not tight but still very little play.
This is what i’ve been using. It’s relatively cheap for how much you get, just standard lower end CPU thermal compound glopped all around the axles and excess squeezed out when the motors are pressed on. I doubt any higher thermal conductive paste would do any better since the thermal mass of the hangars is not huge to begin with, and with paste the hangars get scorching hot before the cans heat up significantly. With more thermal mass on the hangars, I’d maybe start looking into higher thermal conductivity pastes, but there is already plenty of surface area to transfer heat to make up for the shit quality paste imo.
Curious the details of the bimetallic corrosion you’re talking about, where exactly, how bad, etc? Are you looking into paste as an electrically insulating barrier or something to prevent further corrosion?
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Thanks I’ll give that a go and report back! unfortunately I’ll have no baseline at this point though damn 
edit: I have plenty of logs after riding where I toss my board into my garage (temp controlled), maybe I can find a log where I forgot to turn the board off to see the temp drop after a ride as a sort of baseline.
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There are a ton of bushings and bearing mounts in the carvons, and everywhere aluminum interfaced with steel there is evidence of bi-metallic corrosion, every bushing every bearing… when assembling them I’m going to be using some sort of anti-seize for a bandaid, but I got to thinking… if the thermal paste was also low viscosity, perhaps I could get a minuscule thermal transfer and some bi-metallic protection out of thermal paste/grease…
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Did you run into thermal throttle before? If yes and you manage to not run again I’d say it’s enough for now
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That’s what I’m thinking. For how I ride, at 80A motor and 80A battery (FW locked to 60, have to install the no limits FW and push 80/80!!!), after usually the 3.5-4 mile mark temps are consistently high enough to throttle within 5-15 seconds of hard acceleration. They will remain hot enough to throttle relatively quickly unless I reduce throttle aggressively and focus on coasting more to cool down the motors, or stop and take a vape/forum break for 10-15 minutes, at which point I can ride a couple more miles worth of hard acceleration without throttling.
So yes, it’s not killer throttling, it just does require some changes to how aggressively I ride after a certain amount of time. In the end, if the addition of statorade means I no longer have to ride a bit less aggressively or take a vape brake to charge hard the next couple miles, then it’ll be a definite win in my book. Even better, if once I flash no-limits and run 80/80 it doesn’t throttle at any point thanks to this, then an even more solid win. I can’t wait to plot this. Rain needs to stop!
on a side note: does anyone know if flashing (same # version, but standard to no HW limits) fw over TCP bridge is a thing? Vesc tool over TCP otherwise is a godsend.
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Keep in mind that temp reading spikes can occur due to not shielded temp wires close to the phase wires as well.
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