One more question if I wanted more amps I know I can increase the cells in parallel but if I increase the # in series will I get more amps?
No. Increasing the number of cells in series will increase the voltage, but not the current.
Adding more cells in parallel will increase the current, but not the voltage.
Bear in mind though, that adding cells anywhere (more in series, or parallel, or both) gives you both more range, and more power overall.
Series gives more volts,
Parallel gives more amps,
Volts times amps equals watts.
So increasing volts or amps will give you more watts.
Also keep in mind that motor current and battery current are very different things, and they can be set pretty differently. Generally your motor current (this is the actual thing that affects torque) can be much higher than your battery current. 40 battery amps and 80 motor amps are not uncommon settings.
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So roughly speaking
Volts: speed=v
Amps: torque=a
Wats: v*a
But then battery amps don’t really determine torque motor amps do?
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Roughly, yes.
Battery amps affects the maximum amount of power you can have, which affects how much torque you will have while you’re going fast.
When you’re going slow (say from 0-10mph), the motor current affects the maximum torque, and above that speed, the battery current becomes the limit instead.
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Ok so under 10 mph motor amps are the main thing determining torque and anything above 10 mph is the battery amps which come from cells in parallel. And then do watts also mean range?
No, watts is power. Like horsepower.
Watt-hours is energy, AKA range. In the same way volts times amps gives watts, volts times amp-hours gives watt-hours.
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It’s not a sharp transition, and 10mph is just a number in the approximate ballpark. The exact details depend on a lot of factors.
This gets down into motor theory a bit, but I’ll try to keep it somewhat brief.
Any electric motor can also be a generator, converting mechanical energy into electricity, instead of the other way around.
With the types of motors we use generate some electricity even while being used as a motor. This is called back-EMF (EMF is ElectroMotive Force, AKA voltage). The generated voltage is opposite of the voltage used to drive the motor, and increases with the motor’s speed.
This means that at a certain speed, the back-EMF will match the driving voltage, and no more electricity will flow into the motor. The motor won’t spin any faster than this speed, because if it did, it would start generating more electricity than it is using.
When the motor is stopped or spinning slowly, the back-EMF is tiny, and there is nothing but the resistance of the wire to keep electricity from flowing. Since the resistance is very very low (maybe 0.01 ohms or thereabouts), you can get a LOT of current to flow with a little bit of voltage.
This is why at low speed, you can have a TON of motor amps flowing, but notbe pulling a ton of battery current. The ESC basically steps down the high voltage, low current from the battery and turns it into high current, low voltage to feed the motor.
As the motor speed increases, the back-EMF increases, so you need more and more voltage to get X motor current to flow. Eventually there is a point where the power (current times voltage) of the motor would be more than the power the battery can deliver, and the motor current starts to drop while the battery current stays the same.
Basically at low speed you’re in constant-torque (constant motor current) mode, and at higher speed it transitions to constant-power (constant battery current) mode.
Where that “knee” is, depends on all your settings and equipment.
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may be too early for this… but…
here’s a calc i’ve been working on that explains and compares that bit.
dotted line is battery amps
solid line is motor amps
both scaled to torque on Y axis
you can play with settings and see how things change.
oh… and while I was distracged @MysticalDork explains the magic.
The gist of which is at 50% duty cycle. ( ie half speed) the ESC can produce twice the motor amps from battery amps. at 1% dutycycle it can produce 100x more motor amps than battery amps.
so at low speeds your limited by motor amps, then you’re limited by battery amps, and speed.
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Thx for the info I’m gonna read it over in the morning when my brain isn’t dead
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or build some. stuff. skate some stuff. . come think of this 6 months later. 
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Sorry I’m a dumabss what exactly do you recommend doing?
648 is for small gaps
638 larger gaps.
Both are around 3500Nm strength, 638 might just be trickier to get over everything
@YeetMeat
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Can I use unity or xenith for single drive board
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yes
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This board should answer your question.
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Please also read this thread BEFORE u plan on using super single:
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any top-mounted 12s8p 21700 eMTB builds people know of? - am looking for a suitable enclsoure/box that isnt Trampa, and that will fit this battery spec (Pelicase ones seems to only fit 12s7p 21700 max)
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I’m doing 16s6p which is the same amount of cells in this enclosure. https://a.aliexpress.com/_uHKfeX.
When it comes in I will measure the true internal dimensions and let you know if it fits.
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that would be really great if you could. do you remember which one you bought? - there are a few different sized ones.
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280 x 230 x 98 
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