He does bring it up often, but honestly, when I first started researching this stuff devin’s posts actually helped a lot. If you don’t want to see it then don’t read it 
As you said, it was interesting the first time I read it and interesting but it started popping up on threads it did not belong in and that was annoying, but yes, I’ve stopped reading his posts.
ugh. I’m not on the fence it’s raining hard again and I’m fat at my gfs house.
so how much torque does it take to get to 2mph?
Time to bring out my high school physics education…
Assuming you are 80kg have 90mm wheels, and you want to accelerate to 2mph (0.89408m/s) in one second.
F = ma F = 80kg * 0.89408m/s^2 F = 71.5264N
T = rF T = 0.09m * 71.5264N T = 6.437376Nm
Therefor it would take 6.4 newton meters. Obviously take this with the teeny tiniest grain of salt cause its probably wrong…
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pssst, don’t tell anyone:
You can bypass the 200A limitation of the BLDC tool by changing the VESC’s shunts to 0,0005 Ohm and NOT upgrading the firmware. This way the real current is double the commanded current.
If you don’t have these shunts laying around, you can stack two 0,001 Ohm shunts (borrowed from another VESC) to get 0,0005 Ohm.
This is no hoax! I tried it and even have my offroad board running the “wrong” firmware on 0,0005 Ohm shunts because I was too lazy to upgrade all 4 VESCs… (programmed to 60A motor current -> resulting in 120A) x 4 for 4WD
I’m using the new shunts just to be able to rise the absolute max to 240A, to get to get rid of “absolute overcurrent faults” caused by current spikes.
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NO! It can not, because with 0,001 Ohm the VESC does not work properly beyond 160A. (short time peak, not DC)
I see the amp settings value for smoothing out the acceleration more than trying to get a faster start up to 2mph or there about. especially since we’re all pushing to get to maybe 3 mph anyway it doesn’t seem worth it. More so I’d like to see if it possibly smooths cogging at these slow speeds and if the reason it’s cogging at 2mph is because there isn’t enough power
Are you kidding me?!? What do you think showed the picture I send here? Programmer w/ understanding of VESC PC-side software language? - #38 by hexakopter - ESK8 Electronics - Electric Skateboard Builders Forum | Learn How to Build your own E-board[quote=“devin, post:76, topic:15832”]
This seems very pertinent to the topic at hand, I still however have some inkling that he may be referring to -160A to 160A DC… which would mean that the 34A DC MAX expected with 34/200/200 @ 50V @ 0.0415ohm winding @ 1660 watts is well within bounds.
$100 is still on the table.
[/quote]
Good that a destroyed DRV is cheaper than 100$. Go with your 34A DC…
I think you must learn it the hard way.
Then what do you think are the sensors good for?
Making 160A AC to 34A DC for the shunts… 
I think when you don’t go above 160 Amps the VESC will be fine for a while. And if the temperature goes too high it will reduce the power automatically. @Hummie What is the AWG size of the Phase wires. If they are too thin you might shouldn’t do that many times.
That is wrong. That is not how wheels work.
Well, I almost missed Devins lengthy and repeated calculations all over the forum. Almost … 
talking about the mechanical side like @NickTheDude did.
Power used for acceleration can be calculated like the following (going straight, not uphill; this is neglecting friction and wind resistance, wind resistance increases with the square of the velocity). P = m * a * v P for Power in Watts m for Mass in Kg a for acceleration in m/(s*s) v for final velocity in Km/h
if this is all correct, then we have the following examples, all with a 85kg rider / rig
0 to 30km/h in 5 seconds = 1181 Watts 0 to 5km/h in 1 second = 164 Watts 0 to 5km/h in 0.5 seconds = 328 Watts
So what is the issue overall? Don’t think the motor is coughing because of lack of power. In order to use 2000 Watts you would have to go from 0km/h to 30km/h in just under 3 seconds. That’s pretty quick. or from 0 to 5km/h in 0.08 seconds. My logging data shows that I’m using a lot of power when accelerating uphill. So I need the power to go up my long hills and especially when I have to slow down and accelerate again due to traffic.
So not sure what we gain by upping the motor amp limit to 200A?
Ish. But no. @PB1, @NickTheDude So the way to calculate it is you have to use rolling resistance. I think I made a post in some thread a while back.
The reason you cannot neglect friction is because that is literally how wheels work. You assume no friction and you spin your wheels in place. You also should not neglect air drag as that is a big chunk of the power in our application.
Rolling resistance is not the same as static or dynamic friction. So it’s a different set of equations than the ones @NickTheDude used.
But your conclusion is right @PB1, the amount of acceleration to reach 2000W from standstill is idiotic.