Idle Speed Adjustment - Sym PA12B Service Manual

3. Fuel System

Idle Speed Adjustment

Caution
Air-screw was set at factory, so no
adjustment is needed. For easy installation,
count the number of circles it takes to screw
the air-screw to the bottom.
The idle adjustment process must be done
while the bike is on its main stand.
Use a tachometer while adjusting engine
RPM.
Screw in air adjustment screw gently, then
back up to standard circles.
Standard setting：1 ½ circles
Warm up engine fully; adjust the throttle
stopper screw of throttle valve to achieve the
standard idle RPM.
Standard idle RPM：1500rpm±100
Connect the hose of exhaust analyzer to
exhaust front end. Press test key on the
analyzer.
Adjust the air adjustment screw and read CO
reading on the analyzer.
The standard value of CO emission：
1.0~1.5 %
Gradually increase the throttle, make sure rpm
and CO value are within the standard range
after engine running stable. If rpm and CO
value fluctuated, repeat the procedures above
for achieving the standard value.
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Air adjusting screw Idle adjusting screw