Roller doesn’t start.

Moin Moin. Unfortunately, my Kymco KB 50 doesn’t want to start anymore. The spark plug is new and dried. The carburetor would be cleaned. The e-choke and ignition coil have been changed. New oil would be added. The petrol flow also works. New battery has been installed. The only problem I see is that the carburetor is not set properly. Without the engine running I can’t really adjust it. Do you have any tips on what I can do? Paul