Carburetor general tuning guideline:
A) change the idle air-fuel mixture setting 1st.
B) If still not satisfied, change the needle position.
C) If none of the needle position is good, change the jettings.
A) idle air-fuel mixture settings.
1) Air screw set at about 2.5 turns for stock airflow. Modified exhaust + air filterless can use 2 turns.
2) Idle rpm increase a little more than normal.

B) Needle setting
There are 3 ticks on the needle jet.
The lowest tick will give us good FC, as it limits more petrol to flow from mainjet @ half throttle
The highest tick will give us bad FC, as it let more petrol flows from mainjet @ half throttle.

However, highest tick does not mean best acceleration. If too much petrol flows into the venturi, the mixture will become too rich. This will decrease the power at high rpm. So, try different needle clip position and feel which one has the best results.
C) Jet size setting
1) change mainjet to #107.5 (stock #105)
2) change pilotjet to #22.5 (stock #20). If there is no performance increase, then stick back to #20.
3) change mainjet to #110 + pilotjet #22.5. <-- this should be a good pair.