[Big Boi] MBS Comp 90 | 10S4P | 6374 170kV | FSESC 4.12

DIY Builds
#1

This is my second build, the first one is not worth mentioning and lasted less than a week. I’m really new at this and have zero experience in skateboards, i have no idea of what i’m doing.

big boi
big boi2080×1560 1.21 MB

Board

I found a 2013 MBS Comp 90 on leboncoin.fr (french craigslist) for 75€, the guy used it in a field to train for kitesurfing.

  • MBS vector Trucks
  • 8" MBS T3 tires
  • 2 MBS twiststar hubs, swapped two for MBS Rockstar II for the transmission mounting points.

Battery

A friend found a 10S4P bike li-ion battery pack made of LG 18650 MH1, so 12800 mAh. I didn’t asked where it came from and it was already perfectly balanced (insert Thanos meme here).

I put a 10S 60A common port BMS and use a 5A charger, 10 cycles and nothing to report.

shady batterie
shady batterie2080×1560 670 KB

ESC

On my first build i used a prepacked ESC with build-in switch and receiver. This time i wanted to try the VESC so i ordered a Flipsky 4.12 FSESC. Had to find a Korean dude that uploded a VESC tool version that was compatible with it, lot of fun.

big boi inside
big boi inside2080×1560 933 KB

Motor & transmission

A unbranded 6374 170kV whith hall sensor. But a pin of the JST connector broke off so i run unsensored, will fix that next week.

Motor mount and transmission from Overion, the dude is awesome and had everything i needed, even for old vector trucks. The transmission is a 10/42.

box and transmission
box and transmission1560×2080 974 KB

Receiver & remote

Now the shady part. The receiver is an arduino nano with built in RF module.

I looked at many githubs and found the codes to be very good but very complex and with a lot of features i don’t really need. So like most programmers i know, i did y own better shitty version because i think i know more than other people.

So the receiver connect to the remote via the build in RF module and just send a PWM signal to the ESC, keep it simple.

For the remote, i took SolidGeek’s remote and literally switched everything but the thumbwheel mecanism. I use another RF arduino nano and wrote the code for it. I wanted to put a little screen but the battery was too big ><, i don’t have small lipo so i just put a 18650, i think the remote can last 2 weeks between charges.

remote
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Upgrades

  • I want to go dual motor, i actually already bought the transmission and motor mount from Overion to do that. But i’m thinking of switching to trampa VESC or Maytech SuperFOC. Don’t really know yet, it’s quite a lot of money.
  • New remote and receiver. I want to link the receiver via UART to read datas from the ESC and send back to the remote, to display speed and stuff on a little screen. I just have a hard time finding a good self centering thumbwheel.
  • A loopkey, i’m tired of opening the case disconnect the battery, and since it look like a handmade explosive device i could get in trouble.

I never used a skate that big before, i love this board it’s sooo much fun =D. Thank you for all your tutos and posts, i lurked a lot around here while building my board and you helped/taught me A LOT.

13 Likes
#2

Welcome mate.

1 Like
#3

Welcome man! I always sympathize with people who didn’t grow up skating, bought an MBS complete deck for cheap, and want to get wild on it. That is my back story as well.

Glad you’re having a blast with it, it looks good :+1:

5 Likes
#4

Looks good, and it appears the journey will never end. Look forward to your updates.

2 Likes
#5

Regarde juste un peu plus derriere la porte :slightly_smiling_face:

It is coming along really well man. If you wait a bit longer there will be many vesc options.
Just naming a few and then you can do your own research of the forum.

  • neoBOX v4 and v6 (Being tested, soon to be available end of march… The virus slowed down production.)
  • Toqueboards Vesc (unrealeased, but should be soon)

You could look for a unity. If you go really expensive then go trampa not maytech.

Bonne continuation :stuck_out_tongue_winking_eye:

#6

Thank for the warm welcome :grinning:

I didn’t knew about the new batch of VESC comming out, i’ll probably order another FSESC 4.12 to setup everything and swap with the new ones in a few month.

Merci pour le tips :slightly_smiling_face:

I need to work on the lights too, french law says i’ve got to get front and back light before june.

1 Like
#7

Congrats on your board :slight_smile:

Think about getting some HW6 VESCs, apart from suboptimal performance in general, HW4 VESCs reportedly have very non-linear acceleration:

Apart from the lights, is this kind of board street legal in France? :sweat_smile:

#8

Yup it’s kosher, a law passed a few month ago to regulate electric scooters, one wheels, esk8, …

Link to the boring french literature

TL;DR

  • must be at least 12 years old
  • 25km/h max
  • must go on the bike path, and when there is none on the road
  • must wear reflective gear when it’s dark
  • must have insurance, i don’t know the english name for it, google tell me “public liability insurance”
  • and by june 2020, must have a break, lights and some kind of honk :confused:

This thing attract a lot of attention and i pass in front of a police station with it every day :grimacing:, don’t want any trouble.

1 Like
#9

Even with a single motor, that battery might lack for power a bit, especially on mtb. MH1 cells are only capable of 10a per cell. At 10s and 40a, especially with a 4:1 ratio on one motor, your motor is gonna be working pretty damn hard.

Also, the 60a BMS should probably be 40a if you are discharging through it.

#10

I agree, it’s pretty weak in some situations. My biggest problem is going from a full stop, it takes 3/4 seconds to get me really moving, i weight 100kg (220lbs) and sometimes cars aren’t really patients with that kind of delays.

The BMS was ment for a 10s4P of 18650 samsung 30Q, i ordered them from nkon and they are sitting in the box, waiting to be soldered.

Is it really a problem tho, since you can setup a max battery discharge rate in the ESC ? Real noob question here, i don’t want my thing to explode under me with an impatient bus on my tail :stuck_out_tongue:

1 Like
#11

Nah its not a big deal if you are aware of it and have your vesc settings set appropriately.

Many people here bypass the BMS for discharge and rely on vesc settings anyway so its all good.

1 Like
#12

Ok so i messed up. Everything i said about the french law is true, but the catch is in the insurance.

You cannot insure an unregistered electric vehicle. It seems that the vehicle as a whole need to be CE certified, not just parts.
logo_ce

So i’m the happy owner of a 13kg somewhat awkward paperweight. :hugs:, if i bump into someone i’m in deep shit.

#13

Same here in Germany, except that esk8 aren’t allowed at all in any form, just scooters and bikes.
That’s why I built a MTB, so I can ride it off the streets in forests or similar. Riding on the street is too risky.

1 Like