KTM 2009 250 EXC-F SIX DAYS, Owenrs Manual, Page: 86 / 125

MAINTENANCE WORK ON CHASSIS AND ENGINE
84
13.109
Carburetor - idle
600684-10
The idle setting of the carburetor has a big influence on the starting behavior, stable
idling and the response to throttle opening. That means that an engine with a correctly
set idle speed is easier to start than if the idle is set wrongly.
Info
The carburetor and its components are subject to increased wear caused by
engine vibration. Wear can result in malfunctioning.
The idle speed is adjusted with the adjustment screw

.
The idle mixture is adjusted with the idle mixture adjustment screw

.
13.110
Carburetor - adjusting idle
x
600684-10
–
Screw in the idle adjusting screw

until it stops and then to the prescribed basic
setting.
Guideline
Idle mixture adjusting screw (EXC
‑
F, EXC
‑
F SIX DAYS, SX
‑
F)
Open 1.25 turns
Idle mixture adjusting screw (250 XCF-W ZA, 250 XC-F USA)
Open 1.0 turn
Idle mixture adjusting screw (250 XCF-W USA)
Open 1.5 turns
Adjustment tool for mixture control screw (77329034000)
–
Run the engine until warm.
Guideline
Warm-up time
≥
5 min
Danger
Danger of poisoning Exhaust gases are poisonous and can result in uncon-
sciousness and/or death.
–
When running the engine, always make sure there is sufficient ventila-
tion, and do not start or run the engine in a closed space.
–
Adjust the idle speed with adjusting screw

.
Guideline
Choke function deactivated
–
The choke lever is pushed in to the stop.
(EXC
‑
F AUS, XCF
‑
W, XC
‑
F, SX
‑
F) ( p. 23)
Choke function deactivated
–
The choke lever is pushed back to the stop. (EXC-
F EU, EXC
‑
F SIX DAYS) ( p. 23)
Idle speed 1,400… 1,500 rpm
–
Turn the idle adjusting screw

slowly until the idle speed begins to fall.
–
Note the position and turn the idle adjusting screw slowly counterclockwise until
the idle speed falls.
–
Adjust to the point between these two positions with the highest idle speed.
Info
If there is a big engine speed rise, reduce the idle speed to a normal level
and repeat the above steps.
The extreme sport motorcyclist will set the mixture about ¼ of a turn back
from this ideal value (leaner, in a clockwise direction) since the engine
becomes hotter in sporting use.
If the procedure described here does not lead to satisfactory results, the
cause may be a wrongly dimensioned idling jet.
If you can turn the idle adjusting screw to the end without any change of
engine speed, you have to mount a smaller idling jet.
The idle adjusting screw must not be opened more than two turns. If more
than two turns are necessary (rich mixture), use a larger idling jet.
After changing the idling jet, start from the beginning with the adjusting
steps.