How to synchronize a K100 BJ 1990

Hello people need your help. I wanted to synchronize my BMW K100 myself after 25 years. have bought me a part now (see picture) and started. It’s quite good only the 2 cylinders do not react. No matter how I turn the screw. Can you help me? Can I adjust it differently? Can you tell me in which area it should be set in the stand gas or is it enough if they are only synchronous?