Hey guys, planning to build a 4 motor board for added torque without sacrificing speed up steep hills, I have ordered 4 - sk3 190kv motors, 12 - 5s 20c 5000mah lipos to be assembled into a 10s 30 000mah with 4 - focbox speed controllers with 3 - y harness adapters to sync them. A 2.4 wireless controller, led voltage display panel. 60 v capable on off switch. 218 mm v2 trucks with 63mm motor mounts. 15mm bands at 16/36 gearing. 90mm wheels also looking at 100mm. Looking for any input on my build to help this come to life. In total I’ve spent roughly 2500 CANADIAN so far.
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I appreciate the ambition, but 2 6374 motors is already considered overkill. 4 motors is just straight up inefficient (double the drivetrain loss, double the coasting drag) and extremely heavy. We are talking about adding an extra 4lbs of weight here. When you begin carrying your board (for transport, police officer telling you to get off, no ride zones, going up stairs, etc.) you’re going to wish you could shave off a single pound. I own a dual 6374 board, and that shit is already heavy as is.
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BUT then it can have a double purpose, not just a skate, but also a dumbbell
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I presume you are going to switch the power with only a switch, since you mentioned the 60V capable switch. I strongly recommend of using an anti-spark circuit with the switch. Here is one if you want to make it yourself: https://endless-sphere.com/forums/viewtopic.php?f=3&t=40142&start=100
But yea, your board is going to get heavy. You could even make two overpowered boards from those supplies 
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Cheaper and better. Reset lever to turn on. Step on the button to open the circuit. I put one on top of my board(above front trucks), so when I need to shut off the board, I literally just stomp on the switch.
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Where the f*** are you going to fit 12x 5s 5a batteries??? Omg I want to see this board so hard I’m sure you can put together a pretty overpowered jeep with that list
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Interesting. Bit bulky, but good for kill switch. For how long have you been using this?
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Been debated, and yet, still no definitive answer. Using more mores means smaller magnetic fields in each motor. Depending on how much torque your demanding, you could be over saturating your stators by generating too large of a magnetic field for the motor, which is the biggest inefficiency. If 4 motors means you don’t hit this point, then you could achieve better efficiency with 4 motors rather then 2.
Everyone thinks 4wd is super inefficient, yet hummie did 5 miles on my board, and only used about 1/4th of my 8ah battery. Defiantly could have done 20 miles, which is normal for a battery this size.
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@evoheyax Yeah, thats about 17whr/mile which is solid efficiency imo. My 4wd V3 board did 13.5 whr/mile on a leisurely 10mile beach cruise. Ive yet to see any 4wd belt boards efficiency numbers though. @Pychotiller Just finished one, maybe we can throw a BT module on it and get some numbers for comparison?
I have a 4wd spur gear set up on pneumatics and have been doing some efficiency testing as well. Lowest Ive gotten it so far is down to 35whr/mile over a charge cycle and thats with similar riding style to what yeilded 13.5 on the carvon DD’s.
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The problem is theres so many factors in range though. For me, I get 40 Wh per mile on the same board that hummie gets 17 Wh per mile on.
Until someone finally makes the e-skate dyno, and set up all boards to the same battery, same esc’s, and best settings for the each motor, then we won’t know what motors are really the most efficient. I’d love to know though…
In my case, I run them at higher speeds for longer time (so more drag) and probably as a result, I heat them up a bit more. Not too high, but I’m probably losing a few miles just due to the extra heat I generate by riding at higher speeds. Then many more from drag, and even more from my weight. It’s all kinda a guessing game at this point.
For exact comparisons between riders sure, but for basic comparison purposes it seems easy enough. Like when comparing two of my boards for example. Same rider, same riding style, same distance and location, its really pretty obvious which board is more efficient when one averages half the consumption of the other over the same distance.
Works for as long as you don’t drop the entire board on the switch. They’re pretty durable as is.
So this switch is an on off breaker?
How did you assemble the vescs? Using 3 y harness 1 to both rear another to fronts and third to connect the 4 into one receiver?
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I literally won’t have to carry this where I live. I’m in a small town of ontario canada
As far as efficiency, my motors will have less resistance each requiring less power to perform with loads. And at 1200wh 10s 37v battery I don’t think I’m worried even if I dropped to 8 batteries I’d have 800wh 10s 37v
We have one I can put in there. Matt and I will get it set up.
I would love to see a comparison between 4wd and 2wd with the unused motors taken off in fwd and rwd configurations
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I believe the displaced load will act like the difference of 2 and 4d in a car, more traction and lower power consumption/heat in each motor for the same tasks, allowing the ability to gear down from 2.25 to 1 (16/36) to 1.875 to 1 (16/30) and still allow for improved torque during climbs over a standard 2wd. If the upgrade from 1 to 2 motors results in more torque doubling that should theoretically only continue to improve it allowing less energy and friction/stress in motors to accomplish the same things. Also the added motors will provide better breaking as there are 4 breaks instead of 2 for high speeds.
So now I’m fighting with the ideas of connecting a single 10s 5000mah 20c to each motor/vesc individually to protect from overloading the wires to receiver, I realize this lowers my total available mah to 20 000 but wonder if anyone has some advice, am I safe running the 30 000 to all 4 vescs or should i divert the power individually. Will doing so effect wiring my receiver to 4 vescs in parallel?