Carburetor - Adjusting The Idle Speed - KTM 400 EXC EU Owner's Manual

TUNING THE ENGINE

Carburetor - adjusting the idle speed

15.4
x
–
Screw in idle adjusting screw
setting.
Guideline
Idle mixture adjusting screw (All 400 models)
Open
Idle mixture adjusting screw (All 530 EXC models)
Open
Idle mixture adjusting screw (All 450 models)
400341-10
Open
Idle mixture adjusting screw (530 XC-W SIX DAYS USA)
Open
Adjustment tool for mixture control screw (77329034000)
–
Run the engine until warm.
Guideline
Warm-up time
Danger
Danger of poisoning Exhaust gases are poisonous and inhaling them may
result in unconsciousness and/or death.
–
When running the engine, always make sure there is sufficient ventila-
tion, and do not start or run the engine in an enclosed space without an
effective exhaust extraction system.
–
Adjust the idle speed with adjusting screw
Guideline
Choke function deactivated – The choke lever is pushed in to the stop.
(EXC AUS, XC‑W SIX DAYS) (
Choke function deactivated – The choke lever is pushed back to the stop.
(EXC EU, EXC Factory Edition, EXC SIX DAYS) (
Idle speed
–
Turn idle adjusting screw
–
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 large 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 fit 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, repeat the adjusting steps from the beginning.
–
Adjust the idle speed with adjusting screw
Guideline
Choke function deactivated – The choke lever is pushed in to the stop.
(EXC AUS, XC‑W SIX DAYS) (
Choke function deactivated – The choke lever is pushed back to the stop.
(EXC EU, EXC Factory Edition, EXC SIX DAYS) (
Idle speed
all the way and then turn it to the prescribed basic

0.75 turn
1.5 turns
1.75 turns
2.0 turns
≥ 5 min
.

p. 22)
p. 12)
1,550... 1,650 rpm
slowly clockwise until the idle speed begins to fall.

.

p. 22)
p. 12)
1,550... 1,650 rpm
88