i have the same motors and they dont free spin either. They have some serious magnet in them
Yep- free rolling is a total different feeling with this size of motors. A lot of resistance. And mine got hotter than 63xx series too.
Would not recommend these motors for esk8 unless your are:
- A VERY heavyweight guy
- Climbing insane hills/mountains
- Just want to do something insane that most people don’t do
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After coming back home decided that I will keep them… I had some doubts before, but boy that torque… Driving in the road, 5 cars ahead of you driving slow… Small push board jumps forward and overtakes all the cars in instant 
No way I can get this feeling on 6384
Will wait for ARC200 and probably will get another pack of battery for group rides to mount on top when I do need range, for smalls shits I can recharge half of battery in 15mins so I do not see much problem 
Just please HobbyKing make again black friday sale with half price for graphene packs
I am too lazy to edit videos today as I also have to clean up my living room after all the work.
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What current were you running your 6384’s at?
Torque = current / Kv
The 6384’s are quoted as having an 80A max, which is what you are capping these giant beasts at, so you should be able to achieve the same torque levels with the smaller motors since you arent running 80A continuously.
Those 6384 can’t handle 80A without over heating and other issues… Look some previous post and you will understand why I don’t really want to go back to 6384
I am running both 6384 and 80100 at same settings definitely 80100 has way more torque and different response compared to 6384
Didn’t I tell you a while back that you’re not gonna want to go back to 63xx once you go 80xx? Now max out all your settings and start wheelieing at the push of a trigger. It’s a whole new world my friend. 
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Any insight why they consume so much more? In the discussion with @professor_shartsis the final word was that a bigger motor will have way less loses due to more copper, but the reality seems to prove the contrary
Maybe is just because you hammer them all the time since is too much fun? Or they are powerful but a bad eletromagnectic design that lead to lots of iron loses?
Do you speak of motor amps?
Because I got the APS 6384S 170kv and had also the aloy ring came loose on both motors and on the second two magnets “moved out” - but I was also running the vesc6 config with 120A motor amps - did not had any issue about getting hot.
Well motor amps not really matter 
I can set 300A amps and at 0.2 duty it will be only 3kW
?? I must be misunderstanding. Motor amps absolutely matter! Motor torque = kt * motor amps. The whole point of bigger motors is that they allow you to achieve low Kv values without severely limiting your max motor current capabaility. What motor amps are you running your 80xx at?
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Matters but it’s not the one you specified. On specification, max amps are at their working voltage.
Do you expect these motors to deliver 90kNm?
At low duty cycle, (low speed, low voltage) (duty = voltage) For e.g. at duty 0.1 I can send over 500A without an issue because it would be 0.1 * 50.4 = 5.04V and power rating would be 500A * 5.04V = 2.5kW still under rating.
So according to your theories, I should get around 90kNm at ~900RPM?
I don’t remember formulas, but somehow I am a bit in doubt that Torque = Current * kv
I disagree with this. 500A will burn up a motor regardless what voltage it is applied at. Current causes wire to heat according to I^2 R, which is independent of voltage. You can melt a motor very easily without ever breaching its rated power by running them at high current, low voltage.
That is exactly why you can’t get 90 kN*m out of these motors at low duty-cycles. The excessive current melts them.
Full explanation here:
As for torque, wikipedia has a great explanation:
KT is the torque produced divided by armature current.[10] It can be calculated from the motor velocity constant Kv .
You probably haven’t seen raw ESC current consumption spikes 
ESC doesn’t run calculations that fast enough to smooth all current spikes… The current limit is achieved by measuring current and then turning off mosfets if its over the limit, so when you turn on you can even reach as much as motor needs at that moment… Motors don’t run at constant currents to even feel I^2*R effects of those spikes 
EDIT: It’s not much visible for small motors, as they dont have these kind of power needs, but on these 80100 I am getting ABS_OVER_CURRENT with like 280A readings So motor consumes what it needs for that moment until ESC limits it
I’m sorry, I’ve gotten a little over enthusiastic, when really no one wants to read my ranting. Let me step back and just ask what motor current settings you are running your 80XX motors at, and what motor current settings were you running the 6384’s at? I’m genuinely curious to know that.
I was running 90A on both motor and battery Now I stepped it up a bit to around 110A on motor side, I am still looking into the thermals so don’t want to just jump up and blow up my focboxes
90A motor and battery for both the 6384 and the 80100?
BTW, I remember someone suggesting to just crank up the motor amps and let the VESC’s thermal cutoff protections handle the whole burning-output-mosfets thing. I think that might be a valid strategy in your case, since there’s relatively little chance that you’re going to over-current these motors.
Yes for both.
Well like I mentioned, vesc doesn’t handle current limiting really well… I am already getting absolute over current errors with 200A numbers, so I dont want to just burn it. Thermals maybe but still valid option, but somehow I don’t want to spend more money on focboxes don’t have budget for them in upcoming months I have pretty much enough torque right now, definitely way more than it was before I can jump through places where 6384 were not performing
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That is why.
Iron losses are small in our applications, especially with these larger motors than spin much slower.
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Not really if u knew how much force it needs to spin those motors on free roll… If wheel looses friction it freaking slides not spins… I can’t imagine how it would be with lower reduction gearbox… Impossible to pull board
The magnetic force of magnets are huge and it needs current to overcome that… Plus it doesn’t have free roll you let go current and it instantly slows down don’t even need to brake ;D
I filmed the way back from work on helmet will upload later
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