Bends should be2.5x the diameter of the pipe you use. Otherwise the bend in the pipe becomes weaker because it will deform.
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What I am planning is using the rear part of this as the wheel mount (basically the mount the motor is usually mounted to): For BOYUEDA 11 Inch Electric Scooter Dual-Shock Absorber Front Fork Frame Aluminum Alloy High Strength Electric Scooter Accessories Sale - Banggood Mobile) with just a custom mount to correct for the angled mounting spot. Maybe that is an option for you too…
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Question:
How did you figure out what kv value this motor has? I can’t find that anywhere and I believe it is a necessary input when setting up the ESC.
Thanks!
I believe that I derived it from RPM and voltage, but I’m not certain. Divide rpm by voltage to get kv.
Okaaay, fair enough. i tried estimating kv by taking max speed, divide by circumference to get the RPM and the divide by the max volts.
So follow up question (i hope i don’t sound stupid for asking): how do you determine RPM? Is that some vesc gives you when you set the voltage?
(i actually asked the guy selling these motors - he just said he doesn’t know haha)
how many amps would you guess does that thing draw?
That is exactly what I did. Max speed divided by circumference. I believe that if you take the watts and divide by voltage you will get the continuous current. These types of motors have huge burst currents.
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Alright, thanks! 
Gonna let you know how things go!
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You shouldn’t need the KV value to setup an ESC with VESC firmware, but it is useful to know to setup gearing.
If you want to figure out KV there are a few ways of doing it.
Drill method. Put the motor shaft in the chuck of a drill with a known RPM speed (should say on the drill), spin it up and measure the voltage on 2 of the phase leads coming off the motor. KV = Drill RPM / measured voltage
VESC method. Run the motor at full throttle on a bench and look at the “eRPM” value. The desktop VESC tool with the “RT” button clicked is best for this as it shows a more exact number. KV = VESC eRPM / 7 / VESC voltage (may have to add 5-10% to this value to account for the 95% duty cycle limit)
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Thanks!
Fortunately I found a max RPM value on a website and since I know the max voltage I now know that this thing has kv = 27.8 RPM/V
Also no load current is 22A, which means max current would be around 88A.
Gonna try it with a (swappable) 14s4p battery for now, maybe I’ll uprade to 16s at some point.
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