I never get a answer to this question 
but I found my answer, if you are german or can translate form german, have a look on my website SeiteSucht.de
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On Question, I build a Sherp ATV with 4 L- Motors ( each per Wheel ). Now I will use a Tank Joystick Control. 45 Degree turn of the Joystick so far I understood, but where I put the motor Ports ? To steering or to access ? That is not clear for me. Thanks for the answer. Regards, Stefan
[blockquote]J D said:
Hi Tamas,
Many thanks for your help. That has now worked and i am able to tank steer using the Sbrick with a single joystick.
This is what i am using it to control, its a Lego MOC-0678 called Race2 and is designed by Christoph Bartneck https://rebrickable.com/mocs/ChristophBartneck/race2
This is my first MOC that i have made and the Sbrick makes it great fun, my 4 year old loves it.
[/blockquote]
What a great creation! Really great idea, I love it! :) Thanks for sharing with us.
[blockquote]Denis Emery said:
Hi Tamas.
When i use the 2 tracks in same time, to go straight, the motors are not in full power. what can i do?
Thanks
[/blockquote]
Yes, it was a small bug in the Android application. Please update the App, our developers already fixed it.
Hi Tamas,
Many thanks for your help. That has now worked and i am able to tank steer using the Sbrick with a single joystick.
This is what i am using it to control, its a Lego MOC-0678 called Race2 and is designed by Christoph Bartneck https://rebrickable.com/mocs/ChristophBartneck/race2
This is my first MOC that i have made and the Sbrick makes it great fun, my 4 year old loves it.
Hello JD,
I made a short video:
https://www.youtube.com/watch?v=87ThHEaeKaQ
I rotated the Joystick from 0 to 45 degreess.
I also renamed the Channels:
The X channel will be the "Left Track"
And the Y channel will be the "Right Track"
Please do a same profile.
The next step: you need to set up the ports in the application.
Your LEGO modell has two motors for the tracks rights? One for the left track and an another one for the right track. You just need to assign the right track's motor to the "Right Track" channel, and the left track's motor to the "Left Track" chanell.
If you have any questions just let me know and I will help you.
Hi,
I have tried to get this to work seeting up a joypad at 45 degreess, with channel A and B set up to steer the left and right motors, but i am unabel to get it to steer. It only goes forward or backwards with the joypad.
Could someone please explain in a bit more detail on how to get tank steering working using only one joypad.
Many thanks
Here it is a video from Sariel: https://goo.gl/r21TUf
He also control his tank by this "45 degree rotated joystick" :)