I’ve been meaning to get a thermal camera for testing. I will in the next week or two and get a bit more info
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What made you start looking into bearing temps? I’m concerned I’ve been neglecting something on the Rocinante, wondering if it’s worth the hassle to take the drives apart and check the bearings.
Do we have the spec sheet for the bearing available to us?
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I ran Flipsky 6384s at 130 motor amps and broke two of them. Magnets slipped in can and pressed into rotor housing causing them to sieze.
Edit: been running reachers at same amps for longer with no issues. Have Reachers on three of my boards, including my race board too.
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When you say slipped in can, was it like the epoxy/glue giving up and not holding the magnets, or something else?
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I am not terribly concerned about bearing temps.
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Not so much the bearings creating heat at high RPMs, but the motor.
There are two major types of losses in motors. Copper (from running high current through the wires), and Iron (from magnets moving past the iron core).
Copper losses are generally at low RPMs, and iron losses at high RPMs.
There is a sweet spot where the losses are at their lowest in that trough on the gray line.
It’s funny that the sweet spot lands right at 190kv on 12s.
Selecting kv is all about battery voltage.
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Correct.
Interesting. I wonder if that’s the only issue with them temperature/thermals wise, or if there’s still other issues that would pop up. Oh well, already got myself ready for the 7490’s, because my board wasn’t enough of a workout already haha.
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I re-epoxied magnets back in and ran fine for a little while. Then one caught fire haha. Swapped to Reachers and not looked back.
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Well yknow what they say, flames make you go faster right?
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I cant hear you! I’m running 205kv on 16s with a crazy high reduction and there’s nothing you can do about it!
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I can watch your 16s6p drain to 0 in like 16 miles tho 
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I just grabbed a temp gun recently. Was gonna ride around on a hot day cause the front finality bearings get hot to where I can’t hold them
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16s3p, so make it 8 miles
(That’s like 75wh/mi lol)
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Wow! Thanks for such an informative response!
Now I’m wondering where my setup sits.
140kv at 20s, 5.2:1 ratio 8in wheel
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It’s likely really close to that sweet spot
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Sounds pretty ideal, how are your motor temps?
I for sure wouldnt go much lower than 130kv
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My flipsky motors sound like they’re on their last legs, I’ll likely buy whatever the latest SKP motors are available then if 140-130KV is available
I have a decent amount of 138kv 
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