We just call it the air screw ....
It actually meters a small fuel passage, CCW or out means more fuel going into the low range mix.
If you have go to 3 turns or more to get your bike to run right, then change out your pilot jet to the next bigger jet size -- keep on turning it out past 3 turns and it will likely vibrate free and fall out on the street and leave you with an open hole.
(no retaining spring pressure out that far to keep it from moving on out you)
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Seafoam Bill,
Didja know that the addition of 10% ethyl alcohol in regular fuel means any air born H2O type moisture gets chemically assimilated into the fuel (happens automatically and requires no expensive additives such as sea
fool .... oops, I meant Seafoam).
And all commercial fuel contains chemicals to make sure moisture does no harm to the fuel should it actually get in there in any appreciable amount (lawsuits cost too much NOT to do this no matter how cheap the gas).