Mbs f5, 8" if you want to take on the woods, fivestars if you want to try out 9" ever, Matrix 2s forever.
170 kv with 4.9 ratio is fine, I recall you’re light right? I’m running 190 kv on that ratio with 10s and it does great on everything except uphill stand stills.
It’s like I’m on a snowboard going down a mountain of marshmallows
Yes, add a capacitor and use a loopkey and/or run 10S max on 60V equipment (not 12S), 17S max on 100V equipment (not 20S) et cetera for the most confidence
The added capacitor should go physically close to the ESC
Both of those can help mitigate problems from high power conductor inductance / long battery cables.
@rusins could you help me understand why batteries in the backpack would allow for better jumping and less weight? Seems to me, whether on the board or on your back, the weight is still there. In my mind, having it at a lower point, would lower your center of gravity, thus making the ride more stable. I’ve not yet built a mountain board so I’m here to learn with ya. 
IMO gear drive is the best what you can use on a mountainboard.
No 
If you don’t have huge backlash you are save. The only important rule is to never ever brake or accelerate while landing. Especially unintented full brake is very bad. I always stop accelerating before take-off and in best case lift the thumb until I landed. This way you can’t touch the throttle on impact (this happened to me in the beginning).
As @Saturn_Corp mentioned the camber is only there when unweighted. Here some evidence:
That still happens to me on almost every ride 
I don’t fall because of situations like in the beginning but over the time you progress and do more stupid stuff which leads to falls or losing balance. Riding offroad especially on askew slopes (sideways) is very tricky in the beginning.
I also recommend MatrixII and F5.
I am not sure about the backpack, I wanted to make one, too but changed my mind. I think it is much better and easier to have swappable batterys on the deck instead. For riding you can go with the 12s6p and for jumping with something lighter and more slim. The deck might feel better without battery but heavy weight on the back is not the best for jumping for keeping balance.
So please someone design a smart solution for easy swappable packs so I can copy it for my build 
@rusins
I highly recommend taking some time to watch MBS’s tech talk series.
Heres a video about the truck
I would think about getting some 3ds hangers for jumps, I wouldn’t trust mbs and trampa is hit and miss I feel. Just ask @rich 
For jumps I think 6374 or aps 6384 would be good (just battle harden them)
And if you are really aiming for light then lipo might be better. Again @rich is your man
I think I fell in this rabbit hole because my build ended up being 21kg lol (just weighed it last night and was shocked)
Love & respect for pushing the limits!
That’s right, @rusins, don’t forget to get some good protection (especially for shoulders, elbows and butt) . You’ll thank me later 
You plan to pack them together in a separate box or just shrink them together?
Not sure about the back pack thing if you want to go off-roading. Especially not in combination with NESE modules. They still just plastic holders. One big crash and they could split apart and short out the hole pack.
One more thing is the main power wire hanging down from the back pack. You definitely would want to hold the slag at minimum going through rough terrain. When I ride close to trees, bushes etc. I could imagine that the plug could get unplugged because shit catches up in the wires.
The more I ride 9“ tires the more I like that I can just roll over stuff. Not the best for jumping but there is definitely a big difference which terrain you can ride through with 8“ and which with 9“.
It’s very hard to build an Allrounder because something will always be not ideal. Best really to have multiple boards
If I could build only one board I would probably go with
Hearo bro deck
Helical hear drive (1:5ish)
12s6p on the deck with easy swap for 12s1p 5Ah lipos for jump session or just range extension.
Dual 6380/84 170-190kV
Matrix2 or trampa trucks with elastomer damper
Mbs f5 bindings with heelstraps
The new 9“ „plastic“ trampa hubs where you can switch between 8 and 9“ wheels without to remove the hub and save some weight over the alu hubs too.
With trampas carver motor mounts they say you can fit up to 6364 motors but rn i’m trying 6374’s with 6.5mm hand made motor mounts… when I’ll finish them and test fit them i’ll confirm you if 6374 motors fit on the mini trampa trucks. 
2x 6374 is possible with the right mounts on mini trucks. Still wouldn’t buy the mini truck anymore. Definitely not if it’s meant to be real off-road board and not only all terrain.
This. So much this.
That also means when you get home from shredding the gnar, you have another charged board waiting…
Or in my case, one that isn’t broke
After watching a few videos on trucks, I think I’ve changed my mind and will be going with Matrix 2s instead. A set of those should be about 600g lighter than Trampa Infinity trucks, and even Trampa is recommending their barrels instead of springs nowadays.
Pretty set on using MBS Rockstar hubs for weight saving, and no bigger than 8" wheels. I don’t want to ride over things as if they’re not there 
(The trails we’re I’ll be riding are kept up well, won’t be riding through mud or bushes)
And as for the deck – sure, the arch shape disappears when you’re standing on it, but that constant pressure should make it easier to do “mini jumps” I believe, where the wheels still touch the ground, but you’ve raised the middle of the deck up enough to get over a log or something. Flexible deck like that just seems more wieldy to me.
@rich You flexed the deck all the way to the ground in your video, and I’m about the same weight as you. Should I go for a stiffer version then?
Don’t worry, it’s a 14ply carver deck 
The Holypro I have is 16ply and feels right with 74kg.
Every deck has pros and cons. The Trampa deck is really nice for “normal” riding and jumping (if not higher than about 1 meter [3 feet]). With normal riding I mean no heavy off-road (at least not fast). The deck is very comfy and you can ollie/jump-off like a king which is great. On the other hand the deck bends and twists which gives you less control in (heavy) off-road conditions. I rode the HolyPro with Vertigo/Infinity trucks (first springs then elastomere dampers), Matrix II trucks (with red shock blocks) and E-Toxx trucks. All of them felt good on this deck.
Then I switched to the Haero Bro with E-Toxx trucks. It felt good and stable but after some rides I switched back to the HolyPro deck. With the wide deck I couldn’t do very tight turns, I need the overhang of toes and heels. Meanwhile I use the Bro with Matrix II on the Jumpinator II and can steer better with a different technique (more body shifting and less with the feet).
Then I switched to the stiff MBS DWII deck and Trampa trucks with elastomere dampers. The same trucks which were great on the Trampa deck (carvy and stable at speed) are very tricky on the DW II deck, uncomfortable, super super carvy and very unstable. But that’s the only setup which works for me when riding flow trails in bike parks. 
But I often get wobbles and it’s very hard to control especially at speed.
Bla bla bla
just a quick general review for you
Good choice, also get some red shock blocks. Just a hint, they need a bit compression otherwise the lock nut of the kingpin gets loose (This is the case in 3 of 4 Matrix II trucks I have). Actually on 1 truck I have to re-tighten it at least once each ride but I still like the trucks. If you have a 3d printer you could print custom bushings (different flange thickness) if you ever face this problem.
The deck itself is like a spring. When you push it down and use the energy to pull it up you can jump or ollie quite high which is so much fun., for example when jumping up curbs.
At least you should lift the front wheels a bit otherwise if the log or root or whatever is too big you’ll fall. Or better lift both wheel a bit if you are not riding too slow.
First of all riding through mud and bushes is exciting and you should try it both.
From time to time you need to do some emergency jumps so it’s best to practice it. I’ll never forget my first emergency jump when I rode a narrow trail quite fast and suddenly there was a massive tree blocking the way and I had to jump higher than I ever did before. I could clear the tree but crashed on landing, nothing happend. There was a storm the night before so the tree was fresh on the trail which I ride regularly. Another time there was a large and deep hole in the grass which was almost not visible before.
Small jumps are quite easy with the HolyPro so don’t worry
Thank you so much for valuable insight! 
Good to know what shock blocks I’ll need as well Yep, Holypro sounds like just what I’m after
The stock orange ones are also good for carving but for bumpy off-road terrain red is better. Swapping them is very easy and fast.
To be clear, I never intended for that build to be used off-road. You have significant risk of frequent unintended disconnects going jumping with a backpack.
If I were doing this build, I’d do it like @NoWind and @Duffman with the LiPo packs in the middle. If you keep the Wh reasonable, weight shouldn’t be an issue.
Someone has to be the first to try it 
Three tips, 1) have cable slack around the connection to allow for movement, 2) have a solid connection, and 3) wear upper body protection because the backpack can increase the severity of injuries.
