That sounds interesting. Feel free to visit me anytime in vienna so I can try your loose setup 
I really can’t imagine it for jumping or higher off-road speed. 2 days ago I was in the dirt park and compressed the Matrix III red shock blocks even further for jumping. The approach speed is about 35 to 40 km/h. With loose trucks, they turn in immediately when landing and it is very difficult to keep the track afterwards.
I keep my matrix 2s on yellow blocks in the front at the loosest preload. I find that if they are tightened, I hit a bump at speed and the trucks wants to oscillate back and forth between bushings. They can also leave a nasty straight line tipping point on the board. I’m in the loose trucks camp as well but with the caveat of a medium stiff rear bushing setup. Gives the board a very divey, surfy feeling.
Tight trucks makes me feel like this in turns
Loose trucks ridden, less fuqz given!
I might actually take you up on that offer sometime next year 
The BN channels didn’t feel anywhere near as good as the Dualities do though!
It’s alive!
Borrowing my friend’s 21S4P for the weekend, it’s gonna be heavy but at least rideable.
I’m heading to the Halloween event in Cologne/ Bonn tomorrow so no time for a writeup. Should probably start driving 8-9am, it’s 3am now
You mention the BAK 45D cells:
‘They are supposed to be able to peak 126 amps. My plan if all goes well is to peak 100A.’
Where did you get this info from? The website linked says
Current
definition continuous 29.1 A
peak 40.7 A
Which means your 20s1p pack will only be able to provide 40amps max?
The 40A you find is going to be the continuous rating that doesn’t make it reach over temperature.
It has a 60A temperature limited continuous rating.
They tested up to 126A pulses. The internal resistance of the cell makes it believable that it should be able to do it.
I think if you know what you are doing and can build around the cells accordingly to the situation, in many cases it’s safe to go past the manufacturer set continuous limits for some applications like esk8s. Esk8 is a very pulsed application, and most of the time pulses are short enough so that the main thing defining battery performance will be just the internal resistance, not so much the rest of the chemistry.
So, some updates. Finishing up the board
Ended up mounting the trucks with risers, drives setup, cable management done very neatly through some holes that I drilled in the first iteration of the racebro build.
The 12S3P 40T pack that I planned to use until I can get the 20S1P done got a smart BMS installed in a removable way. Unfortunately, it went out of balance in storage, I built it a long time ago from reclaimed cells, but haven’t really used it much recently. The lowest cell is at 2.9 so it should be okay after rebalance but it’s a slow process. My molicel packs stay balanced in storage though…
So for the weekend I had to borrow my friend’s 21S4P, it’s a little heavy but at least it gets the board working.
So now let’s talk about the trip.
Friday night we had a gokart session, nice track for the raceboard. Didn’t use the offroad board.
Saturday morning we had a small group ride on some mountain trails.
100 meters into the group ride this happened and scratched up the gear drive casing.
I accidentally forgot to tighten the nubs with the tool on one wheel… Thought I had the loctite fail instead of lack of tightening, so I just put on the 9x3.5 slicks quickly to be safe it won’t happen again that day.
Riding through some really beautiful autumn forest scenery and going up to a vantage point
Then had an indoor offroad arena for the night
It was super fun, but I was struggling with heelside turns due to the trucks stiffening up deep into the lean, while having wobbles on some bumpy parts. Had fun practicing some jumps, the board felt good in the air. Surprisingly the 21S4P didn’t feel as bad for the jumps as I thought it would be. And the slicks also worked surprisingly well.
Then after a lot of riding this happened:
The motor moved further back, and the gears stopped making contact.
I suspect this might be due to my thermal paste application between the drives and the motors.
I had this happen on the racer previously as well, should be as simple fix as setting up the backlash again. Might remove the thermal paste from the mounting though, not sure yet.
It was definitely an eventful first day for the board!
What a hell of a day of riding you had! I’m jealous 
I do have a cool indoor bike park I get to hit up.
They surprisingly didn’t suck as much as I thought they would 
i was wondering why you were running slicks and how they did lol. have my answer now
@TZDKB was following me around on his EUC a bit and got some footage of this board in the air.
Also battery update. I’ve just ordered a new spot welder. Should be here within a week or so.
It’s the Glitter 811H, 42kW model, 7000A apparently. Apparently powerful enough to do even 0.4 copper directly, but it’s still recommended to do the copper nickel sandwich for optimal strength. That welder set me back like 450$ though on sale - but given that the kweld I’ve been using so far is not mine but my workplace’s and there’s been a few complications there, and I’ve been wanting more performance anyways, it was about time I did an upgrade.
Gear drive update. Turns out the damage is more than I thought, but also easily fixable, as I have some spare parts.
So when I was fixing the board after the 1st breakdown (that was caused because I forgot to tighten the nubs on one wheel) I also took off the wheel adapter plate to clean out the aluminium between it and the casing. During reassembly I managed to over torque 2 of the 3 screws and stripped them out. The previous versions I had didn’t strip from the same torque and I assembled like 6 other sets so maybe these are some softer aluminium, lesson learnt. Then with the threads barely holding, I super glued the screws in place as a quick fix hoping the loctite brand super glue would hold up. It did for the group ride and a good amount of the track time.
But what happened is that the superglue failed eventually and those 2 screws fell out, then the 3rd screw also failed, it was not enough to take all the load. Now one of the POM plates (thanks to @AlexB I have an extra) and the bearing carrier (in which I stripped the threads) are destroyed.
Good thing I destroyed a set of helical gears an year and a half ago. And still had them in my esk8 trash stash. I can take a bearing carrier from that, and I should be able to reassemble everything again. Just need to buy some red thread locker, as blue is not enough for the two bearing carrier screws.
Little battery update. Got a case modelled in 118.80mm length, 30.15mm width. About as small as I can go keeping the printers limitations in mind. 2 of them should fit in the length of the case, but it’s so close I might need to dremel out 0.5mm from the case.
It’s going to get printed in black, not transparent material, the render is transparent just to see the construction.
With the new welder I should be able to easily do the planned 0.3mm copper connections. Apparently even 0.4 is possible with some nickel on top but I think I’ll stick with 0.3 and some nickel.
For the balance wires the plan is to use this connector type with 6 pins (5S). The reason I am not going for JST is that I want the female side of the connector mounted on the pack, with no exposed connections.
Next up a layer above the balance wires I need to figure out how to do the wiring harnesses for the charge and discharge ports. I’d like to get the charge port next to the balance port. The trouble is the discharge - I am already at 77.5mm height. I don’t have much room to play with vertically either, as the XT90 is 10mm height when laid on it’s side… I’ve got probably about 90mm in total space vertically.
Fixed the gear drive, now on the swapped out bearing carrier and wheel adapter. Loctite is curing.
And the 12S3P balanced itself mostly. But the first group seems to act a bit suspicious. I will test it out on the summerboard to see if it behaves okay, don’t want to push it too much until then
I wanna go ride a bit on Sunday if the weather allows. Or next week the forecast looks good as well, probably easiest to borrow my friend’s 21S4P.
Regarding the 20S1P the new spot welder arrived and it’s a beast. I just ordered 0.3 copper and 0.1 nickel plated steel for the welding.
Will probably going to order the cells over the weekend. Need to finish up the 3d model of the modules and start printing soon, but I am a bit busy with university stuff at the moment.
Not sure if I will finish that pack this year
Some work has been done to get this beast into the forest in full glory soon.
Before esk8con I welded up the battery pack to get some more practice on the welder before starting on a larger battery.
Still sits unfinished to this day though. Made it so it’s 4x 5s1p modules if I ever want to fly with it. Will finish it in a couple weeks hopefully, it isn’t the highest priority.
Then now that I have 2 sets of Dualities, I put my old set on here. First just the front without bushings as I’ve been super lazy and my friend wanted to go for a short ride
As long as the wheels all stay on the ground, this feels awesome. The front allows every bit of lean and turn, all resistance comes from the back. Carving at super slow speeds is so much fun on this setup! And completely effortless!
Then today I worked more on the duality swap, it’s 90% done now. Just gotta put in kingpins and bushings, and fix the front kingpin pass through hole. And remount front truck with final hardware.
Running the front hanger inverted for more pivot arm clearance, but it’s also mounted much closer to the tip of the deck, so ride height is still great.
Figured 30/15 will be a good starting point, as I want this fairly turny, while also having good lean.
The bushing setup is something I still have to figure out, but I’m gonna skip lean stoppers completely and probably run Fatcones in the rear, will be starting with Krank formula first to see how that feels. I am usually not a fan of Krank but given that this board will be in the air a fair bit, and fatcones are more divey in nature then chubbies, I think it might be a good setup.
