Hi
I’m looking for motors with more torque, such as the Flipsky 63100. The Factoryk seems to me to be very honest with their specifications, tested with 60 volts and 4 nm. Apparently with more tension they should also generate real torque. Flipsky is said to be apparently not honest with their statements. What do you think ?
I like how they rate the different kv with different power outputs and don’t see that often but their claimed continuous and max wattage seem maybe too close to be real unless with some great cooling. ?
Related to 4nm at 50v doesn’t make sense. If u know the kv and the amperage then you could figure the nm and voltage not relevant.
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Current drawn is decided by load. The current needed to propel you up a hill will be the same for x and y motor for the same voltage. Dsnt matter if you slap a 100kg motor on there, same power needed for the same hill only thing that changed was the extra power needed to carry the motor (not counting losses or efficiency here). The avaible power output will ofc be bigger for the 100kg motor. Assuming you can use it(tow esk8?)
Bigger motor, more mass to rotate and heavier.
Bigger motors tend to get more efficient from a %-perspective. ABB holds the record of most efficient motor (last I looked) but at 99% efficiency the losses still totalled to 1MW or something ridiculous.
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When riding at a constant speed, maybe. But usually in esk8 it’s decided by your throttle 
(Sorry for teasing, I just don’t get what the point of your first paragraph was.)
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Differences are marginal and to be found in efficiency. Bigger is better within margins of practicality. Basically the inverse everything Evolve does. They did a great job strangeling every piece of tech they stuffed into their boards from day one… I can only assume they wanted to increase reliability and profit margins by bottlenecking performance…probably some type of warped theory that could only be dreamed by a landscaper turned board builder… and now look at the market…all they had to do was make the 4x4 available and they probably could have kept their momentum going…I cannot believe they don’t even have a 6375 motor option… WTF…
My question for you is that do you notice a range difference perhaps? Im going with a single 6374 for my new build and was pondering if a 6355 would affect range.
I vaguely remember an old esk8 friend who changed from a single 5065 to a 6374 motor, and said his range dropped.
I wonder if that small difference ends up being offset by the increased weight on the board making it require more power to move 
I’ve not worked extensively with motors myself, so I’d need to do some research to confirm or deny any of what you said. which I don’t have the time to do/ don’t want to bother with
There are many different fields withing EE that require their own expertise / experience. Although there are many older people in the field that have knowledge in many different expertise just due to how long they’ve worked. For reference, even if I were to email my oldest (former) professor and asked him about this question, he’d still likely need to do some research before saying anything concrete on it. Despite having been hired by NASA for several different projects. On the other hand, asking him anything about electrostatics would get you an immediate answer.
It 's good that you’re already doing some research on your own. It may help you find areas within EE that you’re interested in now so that you can make better course decisions in the future once you get to choosing what EE electives to take.
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so if you pull full throttle on the bench, you pull the same current as you would if standing on it? intresting world first!
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Beating a dead horse 
Short story yes : take a rod or an Allen key. Short one and long one.
Use both at extremities with same strength. See which one is easiest to turn the bolt.
Spoiler : the longest one because of tangent force applied to the pivot point 
Same applies for motors, if you can get the tangent vector to be further away from the axle you gain extra torque for free.
Edit : Larger doesn’t equal to wider, it’s the diameter that counts the most
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Kv determines torque for a given current.
Size determines maximum current before the thing explodes.
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Not sure why we’re suddenly on the bench, but yes actually, you can see in vesc tool how motor current shoots up to its maximum value for a split second 
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The motor will do all it can to suck current via the esc.
The throttle simply tells the esc the limit of how much current the motor shall be allowed to suck.
The throttle does not command the esc to force current into the motor.
Load decides how much current the motor wants to suck. On bench, you reach BEMF=Vbatt quick, hence no current can be sucked by the motor when the load is overcome… even if you have 100% throttle.
The current spike on bench is due to load
Inertia.
I know you know all this. I just think I put the wordings so it makes sense… I
Hope.
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I guess you could think of it that way, but what causes the load? Obviously the ESC trying to drive the motor lol
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I haven’t been riding more aggressively since the swap out and I have not noticed a drop in range, I’m not saying it isn’t there but if it is it’s not enough to notice really. I’m also only going from 6374 to 6396 which isn’t the huge jump that a 5065 to a 6374 is.
However full disclosure I did go from belts to gears when I went to the bigger motors but the ratios are super similar. belt ratio was 2.25 and the gears are 2.22. That could be affecting any differences I would have seen of course.
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The motor is shorting the battery via the esc. You control the “severity” of the short circuit with your throttle.
This effect of the short circuit current produces magnetic field in the motor which makes it spin.
The load is always there and as long as the motor cant spin up to 100% duty, it will suck all current it is allowed to do by your throttle command (and current limits in sw)… creating the rotation.
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Those 6396 have a lot of drag, so I’d say the gear drive is compensating for that otherwise I’d be tipping you’d have less range. When people swap from 6396/6389 to the Radium/reachers often they experience a range increase from 10-20% which is pretty significant. Mind you that is going from one of the most draggy motors to least draggy as far as I’ve tested
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For me, the main reason ive ordered a set of reacher 7490s isnt that theyre more efficient in output power to input power, its that i can push more current into them without them catching on fire. The flipsky 6384’s im using right now are struggling a bit thermals wise, and im hesitant to push them above 100A phase as a result. If anyone has any bench tests they can show me how to run in vesc tool, ill gladly do so for you guys to get a good baseline comparison between 6384 and 7490 motors.
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This is an awesome question @glyphiks and to me, based on what little I know, the answer is “we still lack the needed standards” to answer definitively. AFAIK “bigger” when we say “bigger motor” might mean different things to different folks, depending on their interpretation of “bigger.”
Can size is the most visually apparent difference… but do all motors with the same can size have the same amount of copper wound in them? Do they have the same volume and quality of magnet, adhesive, etc?
Like others, My experience has been that larger motors can handle more energy without overheating, but do they need to be larger to accomplish that? I honestly don’t know. I agree with everyone that more metal generally equals more thermal dissipation, but does the material type impact that?
For years people have been hung up on the can length, can width, and KV as the key defining factors that motivate motor selection. There’s got to be more to it than that!
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The larger motor can have lower winding resistance for the same kv. Consequently at low speeds when you’re hitting the motor current limit it will draw less battery current for the same torque. At higher speeds when you’re hitting the battery current limit, it will have higher motor current and therefore higher torque for the same battery current.
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PS If smaller motors were more efficient then Tesla automobiles would use ESK8 sized motors for automotive use.
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