ENGLISH
46
MAINTENANCE WORK ON CHASSIS AND ENGINE
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Adjusting the mixture control screw *
Introduce the special tool on the mixture control screw
[5]
at the carburetor
bottom. Press the tool slightly upward and turn the adjusting wheel
[6]
until
the tool engages the slot of the mixture control screw.
Now, you can go about adjusting the screw. Marks were provided on the
adjusting wheel, making it easier to keep track of the turns.
Checking the float level (float height) *
For this purpose, dismount the carburetor and remove the float chamber. Hold
the carburetor in a slanted position such that the float will abut the float nee-
dle valve but not compress it.
In this position, the edge of the float should be parallel with the float cham-
ber sealing surface (see illustration).
If the float height does not correspond to the desired value, check the float
needle valve and, if necessary, replace it.
If the float needle valve is o.k., you can adjust the float height by bending the
float lever
[7]
.
Mount the float chamber, install the carburetor, and adjust the idle speed.
Engine oil
Automobile engine oil used to be used for four-stroke motorcycles before there
were separate motorcycle specifications. Different technical developments made
it necessary to have a separate specification for four-stroke motorcycles - the
JASO T903 MA standard. Whereas car engines require long changing inter-
vals, motorcycle engines require a higher power output at higher speeds. Most
motorcycle engines also use the same oil to lubricate the transmission and
the clutch. The JASO MA standard responds to these special requirements.
Only use fully synthetic engine oils that meet the JASO MA quality require-
ments (see information on the can).
KTM recommends Motorex Power Synt 4T in the 10W/50 viscosity (for tem-
peratures over 0°C, 32°F) or 5W/40 (for temperatures under 0°C, 32°F).
Checking the engine oil level
The engine oil level can be checked when the engine is cold or warm.
To check, place the motorcycle in an upright position on a level surface (cen-
ter stand).
If the engine is cold, the oil level should be visible at the lower edge
[A]
of
the inspection glass.
If the engine is warm, the oil level should be visible at the upper edge
[B]
of
the inspection glass.
Add engine oil if necessary.
– Insufficient amounts of or low-grade engine oil lead to premature wear in
the engine.
– Do not overfill the engine case.
– Do not underfill the engine case.
0°C
32°F
10W/50
5W/40
JASO T903 MA
TEMPERATUR
A
B
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 Then, use the adjusting wheel to set the desired idle speed.
6 In cases of greater changes in the outside temperature and extremely
different altitudes, the idling speed should be readjusted.
BASIC INFORMATION ON CARBURETOR WEAR
As a result of engine vibrations, the throttle valve, jet needle, and needle jet
are subjected to increased wear. This wear may cause the carburetor to mal-
function (e.g., overly rich mixture). Therefore, these parts should be replaced
after 200 hours.
6
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