[Eljaro]

that is the float level which is incorrect.Adjust that before you do anything else. If the fuel level inside the main well is too low or too high it will affect the emulsifying of the fuel at midrange and you will get what you have now. Now the idle circuit is fine and the main jet probably also, but everything in between, which is managed by the emulsion tube is not operating The Webers do not come adjusted properly from the factory.
Check for aiir leaks around the intake
Also make sure ignition is correct. 12º initial is too little for Webers. More like 20º is best.