How to tune honda Cd70 Euro2 Idle mixture
honda Cd70 euro2 carburetor have air screw for idle mixture adjustment. the best method to adjust a carburetor idle mixture is balancing the air fuel mixture with the given adjustment range.
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 keep turning it quarter turn to the right and wait and check if the engine rpm decreases.
when engine rpm starts to decrease. note that point
now turn the adjuster screw to the left until rpm begins to stumble or irregular.
set the adjuster screw between these two points where engine stumbles or rpm starts to decrease.
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for example :
1 turn is the point where the engine rpm starts to decrease .and 2 turns is the point where engine rpm begins to get irregular. then 2 and half turns is the point where the idle mixture screw should be set.
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Idle Adjustment Screw
Step 3: after adjusting the air mixture screw adjust the rpm with idle rpm screw to 1500rpm.