idk where else to post this
need like a general “powered cold weather vehicles” thread.
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That’s awesome! 
I can already hear people raging that it destroys the ice though whahaha
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Update:
Test 3 tomorrow.
Finally got the power dialed in.
https://www.instagram.com/p/CO3l8N-s016/
Now working on traction.
In progress with casting our own hubs…
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TRAMPA 100/250 21s4p Samsung 40T 100AMP BMS
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I see on that video that the rear tip of the board is scalloped, is it a requirement to clear some space for the paddles? Is it still compatible with standard tipped (round-ish) boards?
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This board has been tested with 15 variations. The first paddles were really close to the tail (why we cut it)
The current design will mount on any board without the cut.
That said… It will be best suited for a high volume short directional board.
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Any stator winding gurus here?
We are making our own and need to figure out optimal windings.
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120Amps made it up to the top of chair 11.
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What do you want to know?
You’re making your own motor? Or just the stator? (have not plowed thru this thread yet)
We have a motor we used as a prototype. It was rated @ 3500w, we need to push to 7-8kw.
We are now going to build our own and need to give the stator vendor winding specs.
So you dont have to figure out airgap and other painful metrics? only how to wind it?
We increased the width of the stator from 65H to 85H and looking to increase fill slot.
Read this : Chosing the right BLDC motor and battery setup for an electric skateboard | Benjamin's robotics 
Figure out what kv you need based on controller and battery setup
Then you can start calculating wire girth etc
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Good read. Thx. (Basic theory understood)
We have a unique situation, 125mm wheel, 275mm paddles and fucking snow.
At this point we will use some trial and error to tune in the system but want to make some educated guesses.
The 3500w motor worked I felt some heat in the Trampa 100/250 @ 120A 88V.
The motor is in freezing conditions and sits in the snow so cooling is good. (Statorade)
We can build a heatsink into the pack as part of the mount for the esc.
We don’t want gears to keep RPM. We are limited in size to keep ridable.
Now that we decided to build our own motors we are redesign hub to reduce diameter to 245mm.
Widening the stator to 85mm will help increase copper considerably.
Looking for a wind to help torque and handle amps.
We will sell 16s-22s high discharge packs.
The goal is to increase the paddle surface area until we can get it to float in powder.
The prototype would do 50+ on flat.
The more speed gained the better the wheel starts to hook up 
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50+ what, km/h?
21S Samsung 21700 30T
22S Molicel P26A
50+ MPH kinda scary goosing it downhill on ice.
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Testing was cut short due to shitty connectors. We have failed 3 of 5 tests with wire connections.
We searched high and low for 8 pin connector that could handle 120amps.
Ended up designing our own from common pins. XT150 & JST 2.5mm
This connector carries current + hall and is “Yank-able”
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I mean no disrespect but based on that photo I think there are a lot of opportunities to improve the efficiency and performance of your packs. This will help in getting more power to the motors for little added cost.
Things like better spot-welding, more weld points per cell, significantly increased nickel-strip width, larger pack wire gauges, etc.
Have you measured the voltage drops across your cell interconnections and overall pack voltage drop under load?
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This was our first attempt at cells. The spot welder sucked… We stopped the packs until we got a better unit.
To be honest we don’t want to build the packs. The black one was sourced but vendors are not very reliable.
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