Pilot Jet Adjustment - Yamaha YZ125N1 Service Manual

SETTING
EC716001
Pilot air screw adjustment
The richness of air-fuel mixture with full closed to
1/4 throttle can be set by turning the pilot air
screw 1.
Turning in the pilot air screw will enrich the mix-
ture at low speeds, and turning out it will lean out
the mixture.
Standard pilot air
screw position
*For EUROPE
EC71R000

Pilot jet adjustment

The air-fuel mixture can basically be adjusted by
the pilot air screw from full closed to 1/2 throttle.
If the pilot air screw is not enough for this adjust-
ment, the pilot jet 1 is changed.
A larger size jet results in a richer mixture at low
speeds, and a smaller size in a leaner mixture.
Standard pilot jet
*For EUROPE
7-4
TUN
1-1/4 turns out
*1-1/2 turns out
#25
*#30