3
To properly adjust the idle speed, follow these steps:
• Tighten the air adjustment screw no. 2 fully and then loosen it up to the value
described in the carburetor setting table (page 12)
• Warm the engine for approx. 5 minutes, until the operational temperature is attained.
• Slowly turn the air adjustment screw 2 clockwise, until idling starts diminishing.
• Mark the position, then slowly turn the air adjustment screw no. 2 counterclockwise,
until idling decreases again.
• Adjust the screw between these two positions, at the highest idling point.
If a remarkable increase in the rpm occurred during the adjustment above, idling
is to be reduced and taken back to the normal level, and then execute the above
procedure.
If no satisfactory results are obtained after the procedure, this may be due to an
incorrect slow-running jet.
If the air adjustment screw has been thoroughly tightened, but the rpm have not
varied, a lower size slow-running jet is to be used.
Execute the adjustment procedure again after replacing the jet.
NOTE:
The correct idling should be between 1500 and 1600 rpm.
CARBURETOR SETTINGS ACCORDING TO THE WORKING CONDITIONS
See the following tables to adjust the carburetor settings according to ambient tem-
perature and altitude.
Legend:
EN
SLM
Above sea level
AVA
Air screw opening (from all closed)
Gm
Slow jet
SPL
Needle
POS
Needle position (from top)
GM
Main jet
VLV
Valve
Standard settings
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