Carburetor Idle Control - KTM 250 SX 2022 Owner's Manual

15 TUNING THE ENGINE
Column 2 corresponds to a needle in the standard position.
Column 1 corresponds to a needle which is half a clip leaner.
Column 3 corresponds to a needle which is half a clip richer.
Column 4 specifies the diameter of the first cylindrical part of the needle. The smaller the diameter of the first
cylindrical part of the needle, the richer the mixture preparation. The larger the diameter of the first cylindrical
part of the needle, the leaner the mixture preparation. The first cylindrical part of the needle has the greatest
influence in the lowest load range.
15.4
102
Info
The top right jet needle A3 corresponds to the richest setting of the carburetor, and the bottom left jet
needle F1 corresponds to the leanest. The optimal carburetor tuning is shown under the respective model.
B00075-10

Carburetor idle control

402799-10
Clip position
1... 5 Clip position from above
The five possible clip positions are shown here.
The carburetor tuning depends on the defined ambient and operat-
ing conditions.
The idle setting of the carburetor has a big influence on the start-
ing behavior, stable idle speed, and the response to throttle open-
ing. This means that an engine with a correctly set idle speed will
be easier to start than one with an incorrectly set idle speed.
Info
The carburetor and its components are subject to increased
wear caused by engine vibration. Wear can result in mal-
functioning.
The factory setting for the carburetor is set for the following val-
ues.
Height above sea 301 ... 750 m (988 ... 2,461 ft)
level
Ambient tempera- 16 ... 24 °C (61 ... 75 °F)
ture
Super unleaded (95 octane) mixed with 2-stroke engine oil
(1:60) ( p. 127)
The idle speed is adjusted with adjusting screw
The idle mixture is adjusted using the idle air adjusting screw
402674-01
1
.
2
.