Zip SSL-25 does not start!

Hello, I bought a zip ssl-25 some time ago. But I always have the test that the morning does not start when it is cold. Got everything Ori and bought me a brand new carburetor so a 10. With a 65 HD. First I had a 74 in it but he didn’t want to start with the 65 hd immediately. Candle was after 10km driving unfortunately still pitch black. I heard if I put the clip from the gas slide further up then he runs leaner is true? And what else can I do I have the mixing screw out now 2 turns. I hope you can help me!