Karma v1 | Apex 40 | Single Turnigy SK3 245kv | 2x 6s Lipo | TB 6s 120A ESC | TB Mount | 83mm Flywheels | Nyko Kama + Wiiciever

Hey all! I’m a longtime ES/ESK8 lurker, DIY enthusiast and web developer living in Sweden. About a year ago a saw a video on kickstarter promoting the "Inboard (or Monolith as it was called then) and I had a project in school where I could research and build anything I would like, so I decided to pursue my dream of having an electric longboard. I had no awareness of this forum at the time so I had too watch a lot of videos, do my own research and ask a lot. (Thanks a lot @onloop & @torqueboards for helping me out)

The board was built about half a year ago and I didn’t want to post until I had some experience, videos and picture to show you all. After learning a lot of the forum I know I could have done things a lot better but for my first build I was very happy. Let me introduce you to “Bigboi”.


Technical Details Top Speed: 41km/h (GPS measured, picture for proof down in the picture section) Range: 4-5km, 8-10km with both packs. (I tend to ride very aggressive, with lots of hills) Battery: 2x 6s Lipo 5000mAh Packs ESC Overheating: Never Motor Overheating: Once, belt was way to tight Wiiciever dropping connection: Sometimes, mostly not very stable connection

Parts Board: Apex 40 (Double Concave) by Original Skateboards (Nose Guards came with the board) Mechanical Kit: Old Version of a welded single mechanical kit from @torqueboards

Motor: Turnigy SK3 245kv Outrunner Battery: 4x [Turnigy 5000mAh 3S 20C Lipo Pack ] (http://www.hobbyking.com/hobbyking/store/__9184__Turnigy_5000mAh_3S_20C_Lipo_Pack.html)(I made 2 packs, each one containing 2 Batteries in Series.) Battery Voltage Checker: 2x HB LiPo Voltage Checker ESC: TorqueBoards 120A 6S ESC Remote Controller: Nyko Kama + Wiiciever Connectors: A lot of 4mm HXT Connectors ( for Connecting packs in parallel and series)

Enclosure: 2x Random Plastic Box MISC; Jumper Cables, 1.5cm Raisers, Blue LED, Banana Plugs, Velcro, Rubber Rings


Pictures

Karma v1

First Enclosure - The heart ESC, Wiiciever, Random blue LED for showing if the board is on and an on/off switch. Power was taken from the Wiiciever

Second Enclosure - The Power 6s 5000mAH Lipo Battery pack with 2x Voltage Checkers with alarm, I carry an extra in my backpack for longer range.

Remote Controller, the Nyko Kama

GPS measured Top Speed

Me trying to hide my smile after finally building the board.


I also made a teaser video for my project.


Lessons I learned

The Good Daaaaaaaaaaamn, this is the most fun, learning experience I have ever had. I had no prior knowledge about building anything like this. I had some basic knowledge about electrical engineering and the physics behind a Brushed DC Motor. But everything else I learned by reading and watching videos from you guys. I learned more in this project than I did in 3 years in school. Thanks a lot to all the people sharing their knowledge and experiences!

The Bad I started out wearing a helmet, gloves and a lot of clothes, but I soon found myself riding without any of these things. That all changed when I read @RunPlayBack article about safety and why it is so important. It really got to me and eversince I have never ridden without a helmet. ALWAYS WEAR A HELMET and never let someone try your board without a helmet.

I learned the hard way that LiPos are not the way to go with Esk8, even though a lot of people use them they wear and tear too fast. (Talking from my own experience) 6 Months of medium-frequent use and they are not as they used to, it’s also time consuming having to charge 4 battery packs when you could just have a LiIon pack with a bms which would just be plug and play after the pack has been built.

Motor mounts, Belts and having a good drivetrain is VERY IMPORTANT. I have destroyed belts having it too lose, not being able to break by having it too lose and stressing the motor to overheating by having to much tension. I also learned that having a wheel pulley that is exactly centered in the wheel is also very important, having it off center by 1-5mm makes the belt too loose on some parts and too tight on others, NOT GOOD.

Don’t weld your motor mount on to the trucks, no room for making adjustments and getting your drivetrain perfect.

The Future I have learned a lot more things and would like to show you how I fixed my problems but that will need a lot more writing. I have planned to make my own website where I will write more about this.

Until next time, ride safe!

17 Likes

how is hill climbing with a single SK3 on 6s?

I’ve been able to climb almsot all hills, and there are alot of hills where I live. However I don’t think they are above 20%. As long as you have some speed starting off everything is fine. Starting from stop does not work though.

Excellent, I admire your pioneering. May I ask what your weight is?

Thanks man :slight_smile: 76kg/168 lbs

1 Like

Nice to see your finished product, good job!

One question though, you said you bought 4x 3s batteries but are only running 6s at the same 5000mah, where’d the other batteries go?

EDIT: nevermind just read you use the 2nd as a spare pack :slight_smile:

1 Like

Be careful with those voltage meters while riding. They draw power from one cell and may damage your lipos. Only use them when not riding. Very nice first build!

Congrats on the build brother and very cool video promo :slight_smile: Wear a helmet next time please :slight_smile:

2 Likes

Hey congrat on ur build.
One question: How did the karma work? any drop out?

ah and i know u don’t want to mess with the hair, but bro PLEASE wear a helmet.

I cannot stress this enough, you need a helmet.

and, u reach 41kph on a 6s board??? HOW COME???

nice build man, thanks for sharing!

@kyo, @lox897, @RunPlayBack, @shred I was a bit stupid at that time, I’m always wearing a helmet now!

@lox897 Didn’t know that :o Why is that! I tend to only plug them in after riding for a while to check how much juice is left.

@kyo The kama feels nice in your hand and the cruise controll is awesome. When giving throttle or braking it sometimes feels like the signal is too weak or that it dropps out. I feel like it is a little bit too unreliable with the bluethooth for esk8.

Run my setup in an esk8 top speed calc and you’ll get something like 41-42km/h :slight_smile:
Weight doesn’t really matter for top speed

As long as you don’t have them plugged in while riding, you should be good.

They are made for checking voltage on LiPos and have an alarm which you can edit. Feels weird that they should damage one cell that hard. :confused:

They draw power from one cell. @lowGuido knows more about it.

Those voltage alarms are alright. I use tjem in all my builds. The tiny amount they draw is negligible. Just balance your pack regularly.

Also solder on your kama dongle.

Alright, so no big problem having them on while riding?

Damn man, nice build!
You gotta ride that beast hard, I’m getting about twice your range for the exact same wh (probably your lipos getting old also) :joy:
I didn’t know those alarms where only powered by only one cell but that actually sounds legit.
Probably no big deal leaving them powered as they can’t draw much current (you could check how unbalanced your lipos are after a long ride just to be 100% sure)