Operation Manual

Adjusting Carburetor
Motor management
Exhaust emissions are controlled by the
design of the fundamental engine
parameters and components
(e.g. carburetion, ignition, timing and
valve or port timing) without the addition
of any major hardware.
The carburetor is set at the factory to
provide an optimum fuel-air mixture
under all operating conditions.
It enables your machine to run smoothly,
be fuel efficient, operate reliably and
produce low emissions.
Standard setting and explanation of
setting pictograms
•
••
•
Check the air filter and clean or
replace it if necessary
•
••
•
Check the spark arresting screen
and clean or replace it if necessary
Turn the high speed adjusting
screw (H) counterclockwise up to
the stop, i.e. 3/4 turn from max.
lean setting
Turn the low speed adjusting
screw (L) clockwise up to the stop
- then back off the screw one
quarter of a turn
Correction of carburetor setting for
higher altitudes
If the engine runs unsatisfactorily, slight
readjustment may be necessary:
•
••
•
Check standard setting
•
••
•
warm up the engine
Turn the high speed adjusting
screw (H) and low speed adjusting
screw (L) clockwise (leaner) -
!
Warning!
If you make the setting too lean, the
maximum permissible engine speed will
be exceeded - risk of engine damage.
Setting idle speed
It is usually necessary to change the
setting of the idle speed adjusting screw
(LA) after every correction to the low
speed adjusting screw (L).
Engine stops while idling
•
••
•
Turn the idle speed adjusting
screw (LA) clockwise until
chain begins to run -
then back off the screw one quarter
of a turn
Chain runs when engine is idling
•
••
•
Turn the idle speed adjusting
screw (LA) counterclockwise until
chain stops running -
then turn screw another
quarter turn in the same direction
Erratic idling behavior,
poor acceleration
Idle setting is too lean
•
••
•
Turn the low speed adjusting
screw (L) counterclockwise -
no further than stop -
until engine runs and accelerates
smoothly -
H
3
4
/
4
L
1
/
H
L
LA
139BA013 KN
4
L
H
3
1
/
4
/
044 39