Turnigy Aerodrive SK3 - 6374-192kv Brushless Outrunner Motor
VERSUS
Turnigy SK8 6374-192KV Sensored Brushless Motor (14P)
The SK3 is more powerful than the SK8 (77A-10mOhms VS 67A-13mOhms)
It’s also lighter! (858gr VS 940gr)
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Turnigy G160 Brushless Outrunner 290kv (160 Glow)
52A - 22mOhms
1 Like
C6364-KV280 EMP brushless Motor for airplane RC Outrunner
59A - 17mOhms
1 Like
Hey I think this thread is awesome. I tried searching a similar thread but didnt come up with anything good. Just a few small threads here and there, most quite old. I got here by finding a single post in thread about a different subject, that led me to vesc project thread on the same thing, then a link that led me back here to this thread. So I changed the title to make more easily searchable.
This is my motor its
Racestar 5065, 149kv, 67mOms.
Its been thrashed for two years so I dont know if that has any effect but the resistance is quite high even for a 149kv motor?
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Considering that the torqueboards 5055 190Kv is 40 mOhms and they have the same size stator, 67 for 149Kv sound about right
As Kv goes down resistance goes up for the same motor
What is the factory kv rating?
Actually not Bro.
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C80100 SENSORED OUTRUNNER BRUSHLESS MOTOR 130KV 7000W
MOTOR: C80100 KV: 130 POWER: 7000W WIRE WINDS: 8D MAX AMP: 200A ESC: 250/300A MAX VOLT: 18S NO LOAD CURRENT: 2,0 SIZE: 80 x 100 ( without shaft ) WEIGHT: 1.980g SHAFT: 12mm with 3mm KEYWAY Accessory pack: Yes Internal PCB with 120 degree hall effect sensors
120A - 9mOhms
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That’s a big boy.
Although I am slightly disappointed in the weight/power ratio.
I would expect more of the additional weight compared to a 6374 motor to go into copper.
This thing weighs 240% more than a 6374 
It is a 130kV though, I would expect a 190ish kV to take even more current.
Good point but you can run it 18S.
Enamel is a real pain to remove, more than on 6374 motors.
It doesn’t look as good as SK3 motors, which are the best quality motors in my opinion (but I didn’t try TRAMPA ones).
You can probably run the other motors in 18s too. Essentially you can run as high voltage as you like provided the insulation in the windings holds up. The problem for us is that most vescs can’t run higher voltages than 12-13s. I had the white 6364 154kV Trampa motors and found them lacking.
How is the new vesc tool coming up with its amp limit and maybe it’s doing what amounts to figuring the motor km? I don’t know what numbers u guys look at but the kv and resistance alone should tell u the motor km or how much heat/waste produced for a given amount of torque and can compare all motors that way: the motor km If someone is good at math and can convert the kv to the kt and then throw the resistance number in then will have the km and we can compare all the motors with that number and only other variable being how well it can rid of the heat produced And iron losses
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It assumes 60W heat losses as a limit for this size of motor, so after measuring resistance and using Ohm’s law it calculates the maximum amps it can take.
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Maytech 6374 130KV are 792gr and take 49A max current (according to VESCtool).
APS 80100 130KV are 2.5x heavier (1980gr) and take 2.4x more current (120/49).
Not that bad.
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True. I hoped a bigger percentage of that weight would go into copper though.
A man’s gotta dream right ? 
Bloody forum, I had forgotten how annoying the editing is here. Single enter for the win.
is the kv really the same and often the kv posted by the maker isn’t accurate. 3mOhms difference is a lot. if they were the same kv then the lower resistance is a hugely better motor with less heat for same torque produced per amp. its like…25% better at doing the job of converting electricity to torque
without having the kv or kt in the equation i dont think you can you compare motors.
this tool only takes the winding resistance into account telling the amount of amps that would produce 60watts of loss but missing the important amount of power that would be coming out with that loss.
and why assume 60 watts loss is a limit of a motor anyway as its not a true limit and arbitrary.
.doesn’t this tool also tell the erpm and voltage like the old tool and can work out the kv?
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While I don’t disagree with anything you wrote, the tool provides easily attainable information.
Yes you can use it to measure the kV if you want.
The 60W as you say is arbitrary but it is a damn good estimate for a motor this size.