ORIGINAL: Chris_RC
Instead of raising the idle, you would want to lean the LSN for a better idle. I NEVER move the idle up or down just because it idles too high or stalls. You tune the LSN then counteract with the idle. So the leaner you go on LSN, you would want to turn the idle out.
No, instead of using the LSN to change idle the LSN should be adjusted for what it is designed and intended to do - to fine tune the transition from idle to 1/4 - ½ throttle where the HSN then takes over. The LSN is not there to adjust or modify idle speed. The LSN adjusts the transition from idle to about 1/4 throttle and above.
Some simple engines only have a HSN. The LSN was created because the engine has different fuel requirements throughout the throttle range - which a single needle cannot accommodate very well.
The HSN should be adjusted before the LSN. Fuel enters the carb through the High Speed Needle first and it directly affects the amount of fuel that goes on to the LSN. The HSN is the first needle to get adjusted, then the LSN is adjusted to get a clean and snappy transition to about 1/4 or half throttle, after which the HSN takes control.
My suggestion to a newb to leave the idle high is that it will help prevent stalling out so that they can get the 2 needles sorted out with less stalling - after all higher rpm requires more fuel and thus a very low idle is easier to ‘drown out’ if the needles are too rich while they are being fine tuned.