Effects of the setting parts on the throttle
Pilot air screw
1 Throttle valve opening
Main jet adjustment
The richness of air-fuel mixture with 3/4 ~ 4/4
throttle can be set by changing the main jet 1.
Standard main jet
1. Spark plug is too hot.
Select a main jet having higher calibrating
No. than standard. (To be enriched)
2. Spark plug is wet.
Select a main jet having lower calibrating
No. than standard. (To be leaned out)
Pilot air screw adjustment
The richness of the air-fuel mixture with the
throttle fully closed to 1/4 open can be set by
turning the pilot air screw 1.
Turning in the pilot air screw will make the mix-
ture enrich at low speeds, and turning it out will
Standard pilot air
7 - 3
T U N
Throttle valve opening
2 turns out