The motors are the cheapest I found on ebay DX2205 2600KV. I don't know if they will work. The propellers are 7x4.5. I ran the setup with more or less equal parts through https://www.ecalc.ch/ with the result that the current will be too high at full speed. At the end I will try this setup and see what happens. My gut tells me it should work 

In fact they are to high. As I said, they were the cheapest and they might work with low timing and the slightly smaller props. If they don't work, the 3s lipo gets hot or what ever I will have to buy other motors. I've got some AGM 2213 935kv laying around, but they are nearly double in height.

They have got double the weight 56gr and the props won't fit. The diameter diameter is 6mm but the props got only 5mm. It seems hard to find small motors with low kv... Perhaps using 2S Lipos with high kv might work. I'll see

Thank you. I'm sorry that I can not continue with this project at the moment. I'm moving and everything is packed in boxes.
There will be progress in the future.
I bought the props from a German eBay seller: http://www.ebay.de/itm/7x4-5-7045-MultiCopter-Klapp-Folding-Propeller-Luftschraube-links-rechts-CCW-CW-/311751916591