Yamaha YZ250F(S) Owner's Service Manual page 626

SETTING
EC71Q000
Carburetor setting parts
Part name
Main jet Rich
(STD)
Lean
Pilot jet Rich
(STD)
Lean
Jet needle Rich
(STD)
Lean
Leak jet Rich
(STD)
Lean
7 - 9
T U N
Size Part number
#190 4MX-14943-45
#188 4MX-14943-95
#185 4MX-14943-44
#182 4MX-14943-94
#180 4MX-14943-43
#178 4MX-14943-93
#175 4MX-14943-42
#172 4MX-14943-92
#170 4MX-14943-41
#48 4MX-14948-06
#45 4MX-14948-05
#42 4MX-14948-04
#40 4MX-14948-03
#38 4MX-14948-02
OBEKN 5JG-14916-EN
OBEKP 5JG-14916-EP
OBEKQ 5JG-14916-E1
OBEKR 5JG-14916-ER
OBEKS 5JG-14916-ES
OBEKT 5JG-14916-ET
OBEKU 5JG-14916-EU
#60 4JT-1494F-11
#70 4JT-1494F-15
#80 4JT-1494F-19
#90 4JT-1494F-23
#100 4JT-1494F-27
#110 4JT-1494F-29
#120 4JT-1494F-31