Yamaha YZ125 2015 Owner's Service Manual page 157

ROAD CONDITION AND EXAMPLES OF CARBURETOR SETTING
Main jet
Jet needle 6BFY44-74-3
Pilot jet A
B
Pilot air screw
A. For USA and CDN
B. Except for USA and CDN
SPECIFICATIONS OF JET NEEDLE
Rich 1 richer
0.5 richer
STD
0.5 leaner
Lean 1 leaner
General condition
Under 10°C 15–25°C
(50°F) (59–77°F)
(Winter) (Spring, Au-
tumn)
#440 #430
6BFY43-74-3
#42.5 #40
#47.5 #45
2-1/4 2-1/4
ø2.72 mm
(0.1071 in)
6BFY43-72-4 6BFY43-73-4
6BFY44-72-3 6BFY44-73-3
6BFY42-72-4 6BFY42-73-4
6BFY43-72-3 6BFY43-73-3
6BFY44-72-2 6BFY44-73-2
6BFY42-72-3 6BFY42-73-3
6BFY43-72-2 6BFY43-73-2
Over 30°C Under 10°C
(86°F)
(Summer)
#420
6BFY44-74-2 6BFY43-74-4
#37.5
#42.5
2-1/4
Diameter of straight portion
ø2.73 mm ø2.74 mm
(0.1075 in) (0.1079 in)
6BFY43-74-4
6BFY44-74-3
6BFY42-74-4
6BFY43-74-3
6BFY44-74-2
6BFY42-74-3
6BFY43-74-2
7-4
Sandy condition
15–25°C
(50°F) (59–77°F)
(Winter) (Spring, Au-
tumn)
#460 #450
6BFY44-74-3
#45 #42.5
#47.5 #45
2-1/4 2-1/4
ø2.75 mm
(0.1083 in)
6BFY43-75-4
6BFY44-75-3
6BFY42-75-4
6BFY43-75-3
6BFY44-75-2
6BFY42-75-3
6BFY43-75-2
ENGINE
Over 30°C
(86°F)
(Summer)
#440
6BFY43-74-3
#40
#42.5
2-1/4
ø2.76 mm
(0.1087 in)
6BFY43-76-4
6BFY44-76-3
6BFY42-76-4
6BFY43-76-3
6BFY44-76-2
6BFY42-76-3
6BFY43-76-2