The idea with using the 2,5mm tail pipe from my walkera 4#3 didn't work because the shaft ends I had proposed couldn't be made so now I am going to try using a 3mm carbon pipe with an inner diameter of 2mm. The standard shaft should fit precisely inside this so there is no need to modify the shaft. I will just have to jut the shaft. It will be interesting how this will work out
If the carbon doesn't work I will go for titanium.
I have also done some other weight reductions that were suggested to me: I have put rubber bands in place of the battery tray and I have cut the windows in the canopy open. The overall weight is now about 236g. It feels as the Lama has become tail heavy so i might move the 4in1 a little forward.
After the weight reductions it seems like I am flying forever This make me want to do even more weight reduction. The flybar is an obvious place to look for reductions.