Next Redux Deck MBS Matrix Trucks MBS F5 Bindings + FX Pro II Heel Straps 4x Mefo Ice Slider 11x4,50-5 on 125mm Gokart rims 4x VESC 4.7 modified with heatsinks, 0,5mOhm shunts, extra TVS diodes and lots of caps 4x c6364 with internal hall sensors 2-stage 8:1 - ISO-04 chain reduction 32W LED headlight 12s30Ah lipo (10Ah+10Ah+10Ah packs) 3D-Printed NRF Hand Controller (VESC NRF Hand Controller)
Just the right toy if you want to have fun when you want to go really offroad:
But let’s go back to 2015 when everything started:
Infected by the eSk8-Virus I wanted to build my own unique board.
When I started this project, the first designs of the VESC were released but not commercially available. So I had to order the PCBs somewhere in Hong Kong and a bunch of electronic parts from mouser and to assemble my VESCs by myself:
I bought a cheap, used MBS Pro90 board of ebay and some MBS Matrix trucks. Unfortunately the board has only 20 degree tip angle so I had to use angled wedges to get good steering capabilities.
As my intend was to go really off road, the ‘normal’ mountainboard tires seemed too small and I decided to use 10" mini quad tires:
Because I tried to build this beast as light as possible I started with quite small Hobbyking NTM-5060 motors. Of the box they have way too high 270kv so i had to reconnect them to WYE resulting in 155kv. To get the desired 40kmh with those big tires I needed a reduction of 8:1 which was easier to archive with a 2-stage chain reduction held together by laser cut aluminium sheets.
Took it to the German eSK8 Championship https://www.esk8b-dtm.de/?language=en but even if the track looks like a desert and the board looks like escaped from Mad Max the smaller boards were better to handle on this course:
One of the first improvements was to get rid of those crappy voltage based battery meters. Instead I’m using this coulometer until now without any issues:
It can be programmed to any battery capacity and to different shunt resistors to match almost any setup. It sits together with a bicycle speedometer in a 3d printed case on top of the VESC enclosure:
VESC with heatspreader soldered to the common positive FET connections, 54V TVS diode on top of of the big ceramic cap. Hard to see under the heatspreader:
The first testride with the new big tires was a lot of fun, but they were throwing so much dirt at me that I had to build fenders. Therefore I had the mounting plates cut from 4mm Alu and the fenders from 2mm Alu and bent to shape:
I rode around 500km offroad over the summer 2015, when fall came and the days got shorter and darker I had to build a proper headlight. Before I had done some experiments with flashlights but was never satisfied because there was always too much light directly in front of me and always to less light in the far field and in the corners. I found the perfect solution in a 32W (105 lm/W) high power LED strip in combination with a cylindrical lens.
To power the LED I’m using a Meanwell LDD-1000HW - a current regulated 1000mA 56V step down regulator which is located in my ‘cockpit’ (black brick in the lower left corner of the last pic):
Because the new tires are gocart winter tires and can officially be equipped with spikes I simply had to try it and bought a 1000pcs set of ‘screw in spikes’:
In 2015 we had 2 weeks of snow (and 2 weeks of fun!!!), afterwards I simply screwed the spikes out and was ready for spring again. Unfortunately we had no snow in winter 2016 so I couldn’t use them again…:
I wanted rearrange my VESC and cap wiring because I found out on my other builds that short connections and good ESR can keep your ESC cooler and improve your reliability. To keep wires short, I had to stack the PCBs and the caps and just filled the remaining space with more caps…
No matter how many caps you add, they won’t help you with voltage sag, but can compensate for the inductance of long battery wires, which would induce high voltage spikes when switching at high currents.
I’m running 12s 10Ah (3x 4s5Ah x2) per ‘layer’ and can stack up to 3 layers for 12s30Ah. Everything at 20c constant / 30c burst.
To power everything up I simply use an XT90S antispark loop key with a little 100A ANL fuse
This holds up very well against the 250A burst current I am pulling at maximum like in the beginning of this video:
I always forgot to show you one little detail, which imo is a big improvement over the stock MBS spring truck system.
Instead of using a spring and an egg shock (dampa), I’m using an elastomer compression spring to get better / softer steering capabilities and better dampening of speed wobbles.
This is a comparison of the usual spring/damper combination and elastomer springs:
I’m running these in my Monster an in a Trampa/Next crossover board of a friend for more than a year and am totally satisfied with the feeling of the ride.
The small NTM5060 motors survived the torture but were upgraded for beefier, diy sensored c6364 motors. Bigger motor won’t fit because of the headlight and wold also crash into the deck while turning.
Nevertheless they take 120A motor current very well and don’t even get warm in this 4wd setup:
The duff monster…
…and cheap!! 
