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Carb needle settings.

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K2-K6:
Deltarider,  it looks like that information adds as much confusion as it does clarity to the question.  There's too many provisions to make changes to come out with any degree of certainty.

The adjustment for both needles and airscrew are effectively a response to local average barometric pressures (generally oxygen content) and designed into most carburettor to facilitate this,  else you'd be forced to swap jets to fit the engine within it's market location. 

The overall jet size makes the emission level as designed ( essentially an absolute unless changed) with adjustment made within that to facilitate local variance of air component.  If they've done this thoroughly the adjustment will usually sit at mid range with specific advice to differ IF experience like flat spots were obvious. I don't feel they are ever given as absolutes though,  merely advised and qualified starting points.

The airscrews particularly don't change the total flow of an idle circuit,  just the gradient of change and it's starting volume at lowest rpm.  Maximum flow is fixed as that of the jet bore,  but the position of the airscrew alters how much of that flow is delivered at the lowest venturi flow. 
Airscrew further out just drops the "floor" % to start,  but it'll still flow the same as it gets to peak flow of idle circuit wherever you place the screw.
Airscrew fully in,  the idle jet will just flow at maximum as soon as you start the engine with no noticeable gradient. 

Given that it's not clear within generally available advice,  it's realistic to start the needles in the middle position I feel.

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