How to tune honda Cd70 Euro2 Idle mixture
honda Cd70 euro 2 carburetor have air screw for idle mixture adjustment.
Front or engine side
Adjustment Screw Side
Air Filter Box Side
Step 1: adjust the idle speed with idle screw to 1500rpm. turn the screw right to increase engine rpm and left to reduce it.
Turn Left to decrease the Engine Rpm
Turn Right to Raise the Engine Rpm
Idle Mixture Adjustment Screw in this case ( Air Screw)
Step 2: turn the idle air mixture screw left 1 and half turn for adjusting to factory setting.
then from that point turn it half turn right and wait and check if the engine rpm increases.
if not then turn it half turn left and start from the factory setting and then turn half turn left and check for rpm increase.
if rpm increases then turn half turn more and keep turning till you find maximum rpm.
its maximum limit is 3 turns after that air screw won't affect the air supply.
if it does't increase after 3 turns then keep it on 3 turns out
Idle Adjustment Screw
Step 3: after finding the highest rpm with air mixture screw adjust the rpm with idle rpm screw to 1500rpm.