Idle mixture
 

Just want to settle a friendly discussion. Will the idle mixture screw affect the high speed needle setting on a glow engine like it does on gas engines? Or does it depend on the brand engine. (the one in question is a Saito).

Idle mixture
 

On carbs with dual needle setups, yes... generally speaking.
On carbs with air-bleed idle mixture control... no.

The air bleed carbs merely open/close a small hole which allows outside air in.

On the others, the low end adjustment also affects the overall fuel flow for a given throttle position.