Iām also wondering how duty cycle plays into this. if battery amps is still limited to 100A, the actual power youāre delivering to the motors is still limited if feels like that must limit heat.
but i could also think of it as the more torque demanded at lower dutycycle and thus higher phase amps the more of that 100amps battery power goes towards heat vs rotation.
<l_max_vin>59</l_max_vin>
This might be problematic at 20S?
thanks. these are wrong settings. didnāt pull correctly. fixing.
ā¦
And fixed.
The reason phase amps can cause rapid heating of motor coils despite conservative battery amps is because a motor (which is an inductor) + ESC works as a form of buck converter. When youāre running at 50% duty youāre not just delivering full battery voltage 50% of the time, because the motor smoothes the spikes out its actually dropping the voltage down and increasing the current, so the āmotor currentā is actual current and actually continuous from my understandingā¦
you think running 5.2 is better than 5.3 if iām not ready to go to 6.x ?
Change the gearing for short track. (Shorten motor shafts while youāre at it)
for comparison my reference āshort trackā gearing on SRB has been 49mph (8s 800kv 10/78 95% loaded ) This comes from the fact that gearing down further than the 10T is impossible without a 2 stage. long track is 11/78 for 54mph
Dashās is geared for 48.9 which is why i was leaving it that way to compare.
were you suggesting even further down that that? I wouldnāt be able to do a fair comparison. but itās true that so far iām only bursting to 30mph on short track as I havenāt gotten comfortable with it. and i rarely hit over 40mph on short track on my SRB
heh. yah this bugs me. 
I have to make sure dash is ok with me cutting his motor shafts.
or maybe @Skyart or @Tony_Stark want to send me some 245kvs for some peak amps?
245 * 20 * 4.2 * 7 = 144k erpm? should work no?
Iāve tried on 18s, but have not tried 20s yet, I have exactly 2 of these 245kv left lol
The calculated ERPM is going to be higher than your actual ERPM for various loss reasons, I think you should be around 130k and itās possible it will work out ok, 245kv motor might also handle 200amps a bit better
Throw on some 17t. (You would get higher in the erpms more easily which idk if it is a bad thing )
I have zero interest in finding out if full speed on the road will cause me to eat shit or not due to this. Too pretty.
obvs. this is the bane of vesc. no one trusts anything
for clarity. which fw version are you saying doesnāt cause you to eat shit? and which are you saying might and you donāt want to find out?
5.02, 5.03, 6.02
I thought 5.02 formerly had all the trust?
5.2 / 5.02 (hate how they do that) has been solid for me with no weirdness.
5.3 / 5.03 had the full throttle flutter on the bench and I said no thank you.
Wanted to try 6.X but it kills the robogotchi functionality so havenāt pursued it.
Pick your poison, but Iād go with 6.02 first, just for flexibility of running sHFI if your sensors break. Iām on 6.0 and it has been flawless. If the freespin is funky or if you get faults, then Iād try 5.2 and 5.3.
FOC observer changed significantly between 5.2 and 5.3, but like pretty much everyone else, I have zero fucking clue what that actually means.
No they will just overheat lol. Iād stay below 15k rpm no load, and even below 12k if you want usability on days over 30C / 86f.
Meaning The ESC will overheat? that from switching speeds?
12k / 20 / 4.2v = 143kv
15k / 20 / 4.2v. = 179kv
so far by feel at 151kv i need at least 150A motor/side on the low end to get close to the pull of the SRB castle setup. in the 0 - 60% of top speed range.
hmm.
I think you will be ok with 245kv for a few hot laps, but yeah it will heat up faaaaast
Here is what happens to 300kv at 18s unloaded
This is 22k rpm
Your motors will heat up fast, however the fan in these is great and if you can keep your speed upā¦it will likely be good for a few laps at AVS
love that you did that experiment.
so the ESC seemed to do pretty well heat wise.
Iām actually confused where the no load heat in the motor is coming from? i notice battery amps are low in the experiment. are you both saying motor heat is a function of erpm? definitely something for me to learn here still.