Finally I had some time to finish the second motor, board itself and electric stuff:
And actually it ran nice and smooth:
BUT
After a short ride (before snow fell, the first time this year…), one motor gave some kind of creepy grinding sounds. So I stopped testing and carried Frankensteins monster home 
Between the aluminium sleeve support and the stator of the motor had gathered some aluminium powder… grinding traces weren’t hard to find 
Explanation:
The thinnest part of the aluminium tube (as sleeve support) is 0,5mm thick having a gap of 0,5mm radial to the stator. I knew that this would be the Achilles’ heel of my design but I expected the hard PU and aluminium to not bend… and it didn’t…at least on one side…but on the other side it did 
Anyways, I always wanted to cast my own hub sleeves where I can have a thicker support and more space for an aluminium tube 