Air Fuel Mixture

Does anyone know the factory air fuel mixture setting for the 91 b2200 carburetor? I had a shop adjust the carb because i was burning too much gas and they took out the factory plug and adjusted it. I went to look at the screw as my mileage it around 270km a tank on a fully rebuilt engine "not good". It appears the screw is so smooth that it may have moved from the vibrations of the engine. In addition to that i failed aircare yeaaahhhhhhh. So any tips on that would be appreciated as well.

Thanks

air/fuel mix is adjuster bt the "computer on Bseries.Try changing ur o2 sensor.BJ