Electric kart

[LuigiDesign]

It is a good charger,

I made a portable dual charger station, the good thing is it´s very accurate reading mV, IR, and regenerate energy features, meaning that you can discharge some cells to charge another cells...

PS: Be carefull when you connect both output channels to the same cells string. Sure that will be damaged. (Trust me )

[nuxland]

Tested how limiting power is affecting motor temp and used energy. And as Latvia has now official electric kart class (two of them, one 15kw and another open up to 25kw) then it was time to test it.
Motor temp were under control with 250A battery limit but lap times were 3sec slower. Also about 1,6Ah went to one lap and without limit it was 2Ah. So 15 laps is possible only with my bigger 40Ah battery. With 25Ah battery i would only use then max 12 laps.
First test ride and i blow a tire in 11th lap. Also it seems that bigger battery cells that I did not replace were sagging more then the new ones https://www.youtube.com/watch?v=Rvrq568 ... dpw03c010c

[Punx0r]

That is all kinds of cool!

[futurerel]

Where did you buy a 36 teeth rear sprocket? I've been looking to match your gear ratio to get the same speed as I have the similar motor specs as you.

[nuxland]

Hey

Tested VBOX sport in weekend, better than my cycle data logger gps
https://www.youtube.com/watch?v=nZ65BTSk4lI

[LuigiDesign]

Futurerel:
On ebay you can find them up to T36 for 428 chains on 50mm axis. https://rover.ebay.com/rover/0/0/0?mpre ... 3144172397

Nuxland: 20Hz GPS is a very smooth device... Good purchase! You are in a next level!

[frodus]

Do you have more information on the telemetry you've designed? This is super interesting. I'm using Sevcon and considering the same BMS.

Is there a project for it somewhere?

[nuxland]

Do you have more information on the telemetry you've designed? This is super interesting. I'm using Sevcon and considering the same BMS.
Is there a project for it somewhere?

For olimex there is project in https://bitbucket.org/elektrikardid/ but it is not public. But you can't use that for telemetry because olimex clock was faster or slower than real clock and data went out of sync with video, cant remeber.
But for windows computer I have programmed in c# a winform application that is communicating over canbus via can adapter.
The program is a prototype, but it reads sevcon data and also sends questions to bms for the data.

[nuxland]

Took some time and parcipated an amateur karting event. They let me race with soviet era karts. There were two classes "Retro N" that is all soviet (frame, motor even the tires are old, made last century). And ´"Retro A" where you could use new frame and tires and even modifye motor a little bit, but motors were soviet made Minsk, CZ or MZ. Reason for me racing with them and not in open class with rotax karts was, that retro had 10 laps but rotax 15. And for me 10 is max i can race.
I had worn rear brakepads and brake fluid started to boil in 7th lap in first race so last 2 laps were without rear brakes. Then I got a little better pads and next two races it almoust worked 10 laps
Tested also a cheap ACME 360 cam, so here is two 360 youtube videos from race 1 and race 3.
Race 1
https://www.youtube.com/watch?v=pqyI7Jb8yg0
Race 3
https://www.youtube.com/watch?v=HKf28E4GMgE

[Upperfoot]

That's a shame about the 10 laps limitation, that's because of the motor temperature right?

[fechter]

Great video! Looks scary as hell. From a standing start you really out pull those two stroke gassers. I see the kart doesn't do so well on the grass.

Are you using regen? It didn't show on the display. It might help keep your brake fluid from boiling, but will add to motor heating.

[frodus]

Nuxland,
looks awesome! How was the heat on the motor? What motor are you using right now? I had forgotten which you settled on. I'm considering the ME1507 for testing, and ME1616 if I went to race.

BTW, Hadn't heard from you on the software side of this project, and Jose (e-vektor) is working on an OBDII converter for Sevcon and Zeva BMS. So far it's working and we can see things using Torque. We chose this direction, since torque can do video overlays, logging, and upload to a server if needed.
More info:
viewtopic.php?f=7&t=95067

[Ralyant]

Bump, I need updates!

[nuxland]

have had no time in months to do things i want Also have not driven this summer at all and that is sad...

But designed new fixation for my batterys and started to implement these.
It consists of one round metal and one flat metal that go inside each other.
Here are some images that will explan how it will work, but the goal is that I only have to unscrew locking bolt and disconnect wires and then I could change one battery to another just by sliding one out and another in.

[jonescg]

TANK!

Loos awesome!

[nuxland]

I would say that now fast fixation is 99% done. Just have to find time to test it out in the field this year.

https://youtu.be/TljsV2ZlSLQ

PS! found this metal bar under the table and it suited just fine to help me to install and remove the battery. It gave me just the needed force that i could not give with my hands

[Pota]

How did you make and create those battery boxes?
How did you connect those clear plastic parts to the alu?

[nuxland]

For bigger 40Ah and 4kwh battery i do not have separate thread (I have in this thread some pictures).
But for 25Ah and 2,5kwh battery i have a separate build thread: https://endless-sphere.com/forums/viewt ... 14&t=85912

There is also two youtube videos about these battery-s.
Bigger and smaller: https://youtu.be/8UUFCh3wtCI
Only Small: https://youtu.be/CDkn4za6Rig

PS! I'm also building a third battery and build thread is here: https://endless-sphere.com/forums/viewt ... 14&t=97763

I hope these links answer your questions

[louis raaijmakers]

hey nuxland,
seriously coool posted. i have pulled the trigger and bought some cool parts.
and bought the same parts (motor and controller) u are using.. (sorry but it is so cool )

any chance you ar willing to share or sell your dcf file?

greetings louis

ps:i will send you a pm if thats oke?

[hallkbrdz]

With your experience, what's the best way to attach the battery support to the frame? From what I can tell from photos, you have a solid tube front and back where the stubs for the sidepods used to attach. Did you just use a larger diameter tube to go over the original one, cut and replace the original stubs, or what?

Also, does the hanging the battery weight on the single left tube of the frame cause any odd handling issues?

[nuxland]

Yes, i have rewelded the sidepods and using larger tube that goes over the frame.

sidebars.jpg (447.68 KiB) Viewed 888 times

And i used 5mm aluminium sheets so I could place my first battery cells "winston 60Ah lifepo" 16pcs in left and right.

sidebumperholders.jpg (226.64 KiB) Viewed 888 times

With my lighter 37kg small lifepo4 pack left and right side are the same as I have in the right ~23kg motor with mounts and ~10kg controller with cooling.

If I would start with a new frame I would do i differently. I think some round or sqare aluminium tubes that sits on the frame and go from left to right under the seat. And connect with some clamps. It would be lighter and still allow frame to bend in corners.
But still i would use battery in left and controller and motor in right.
Also my current setup is to low and i have to replace some intube nuts because they worn out as seen in this picture (do not look at red circles, I have an old frame and it was worn in that places so I had to reinforce it).

framebent.jpg (251.85 KiB) Viewed 888 times

[hallkbrdz]

Thanks, those photos really help a lot.

I was also considering running aluminum tube supports under the seat for the smallish lipo pack I am building. I think that arrangement should work well and keep the frame reasonably flexible.

[nuxland]

Went to race lately, it was special race as we used obstacles and only 3 laps each race. All together 1 practice and 3 races.
I used at practice and first race my lipo battery and 2nd and 3rd race my smaller lifepo4 battery. There was no elecricity in that track
And it seems that lipo has more power (that is obvious)

Lipo practice: https://youtu.be/-JImaewEbJo
LifePo4 2nd race: https://youtu.be/DAhWZI-h0Ls

And it seems they got me in this video also with lipo pack in the kart: https://youtu.be/A4nFH05x6pM?t=155

[hallkbrdz]

Looks good!

[nuxland]

Did modification to my windows logging software, so it could now automatically detect what battery pack is installed.
There will be endurance race at the end of month, 50 laps in a 1km track.
I need to cap my performance so that i could drive 50 laps and not overheat my motor.
But with my calculations and test (I tested 25kw gap in the same track and got 1,6Ah or 160wh per lap) I would consume about 80Ah or 8kwh of energy. My pack are following 1st LifePo4 40Ah and ~4kwh, 2nd LifePo4 25Ah and around 2,5kwh, 3rd LiPo 35Ah and around 3,5kwh. So all together 100Ah or 10kwh but i have to consider that I can not drive them completly empty either.
So with 40Ah I'm assuming 22 laps, 25Ah will do 12 laps and 35Ah lipo will do 16laps. I will use a friend who will monitor remotely cell voltages and he will inform me how many laps I'm driven and all status.
I also hope that changing battery will be quicker with two people.
Here is a video of my doing first test of battery changing and automatically detecting batterys.
[youtube]MvVc7K1d14s[/youtube]