ENGLISH
30
60°
0,8 mm
1
2
3
4
5
CARBURETOR – Adjust idling *
Idling adjustment of the carburetor strongly affects the engine’s starting
behavior. That is, an engine whose idling speed is adjusted correctly will be
easier to start than one whose idling speed has not been adjusted correctly.
Idling is controlled by the throttle stop screw
1
and the mixture control
screw
2
. The throttle stop screw is used to adjust the basic position of the
throttle. The mixture control screw is used to control the idle mixture which
arrives at the engine via the idle system. Turning it clockwise will reduce the
amount of gasoline (lean mixture), turning it counterclockwise will increase
the amount of gasoline (rich mixture).
TO ADJUST IDLING CORRECTLY, PROCEED AS FOLLOWS:
1 Turn in mixture control screw
2
up to the stop, and turn it back out by
1.5 turns
2 Warm up the engine
3 Use throttle stop screw
1
to adjust normal idling speed (1400-1500
r.p.m.)
4 Turn mixture control screw
2
slowly clockwise until idling speed starts to
decrease. Memorize this position, and turn mixture control screw slowly
counterclockwise until the idling speed will decrease again. Adjust the
point of the highest idling speed between these two positions. The hig-
hly competitive user will make his adjustment 1/4 turn leaner (clockwise)
because his engine will heat up more in competitive use.
NOTE: If you fail to obtain a satisfying result by following the procedure
described above, an incorrectly dimensioned idling nozzle may be the
cause. In case:
a) the mixture control screw has been screwed in up to the stop without
causing any change in rotational speed, a smaller idling jet has to be
installed;
b) the engine dies when the mixture control screw is still open by
2 turns, a larger idling jet needs to be selected;
Naturally, in cases of jet changes, you have to start your adjusting work
from the beginning.
5 Now, use the slide stop screw to adjust the desired idling speed
6 In cases of greater changes in outside temperature and extremely
different altitudes, the idling speed should be readjusted.
Basic information on carburetor wear
As a result of engine vibrations, throttle valve, jet needle, and needle jet are
subjected to increased wear. This wear may cause carburetor malfunction
(e.g., overly rich mixture). Therefore, these parts should be replaced after
10.000 kilometers (6.000 miles).
Adjust hot start device *
If the hot start button was removed when cleaning the carburetor, re-adjust
the hot start device.
Install carburetor and adjust idling as discribed above. Then unlock nut
3
,
press in hot start device
4
and adjust engine rev with adjusting screw
5
to
2.000-2.500 rpm. Tighten locking nut.
Check float level *
Stand the carburettor diagonally at about 60° so that the spring in the float
needle valve is not pressed together. In this position, the edge of the float
should be parallel with the float bowl sealing surface (see illustration).
Checking axial play of float *
For proper functioning of the float, there must be an axial play of 0.8 mm
(0,03 in). If necessary, slightly abrade and deburr lateral float guide.
