Lister D carb setup

Is there a basic procedure for setting up the carb on a lister D? IE when do you know when the valve air stem (dont know its proper term) is set correctly, the bit that controls the spring for rise and fall of the air valve?.

Just put it together and fit to the engine, nothing special needed, the valve air stem opens when the cylinder draws air, the spring only needs to be light to pop the valve shut.

Maryalice