Suzuki RM250 Owner's Service Manual page 53

4-8 MACHINE TUNING
Jet needle
Air/fuel
SIZE
mixture
Lean NECL
NEDL
NECK
NEDK
NECJ
NEDJ
NECW
NEDW
* NECH
NEDH
NECG
NEDG
NECF
Rich NEDF
NOTE:
SHADED: STANDARD
*: INCLUDED ALTERNATE PARTS
NONE: OPTIONAL PARTS
1 Adjustment of slow system
1) Set the air screw as specified.
2) See if the selected slow jet is correct or not by
judging the air/fuel mixture. If air/fuel mixture is
rich, replace it with smaller one. If air/fuel mix-
ture is lean, replace it with larger one.
Ex. Slow jet #50
If air/fuel mixture is rich, replace it with #48
slow jet. If air/fuel mixture is lean, replace
it with #52 slow jet.
2 Adjustment of main system
With the throttle opened 3/4 to full, make main sys-
P/NO. tem adjustment monitoring the air/fuel mixture con-
dition after completion of slow system settings.
13383-37FG0
* Make sure to adjust the main system before
13383-37FP0
13383-37FF0
13383-37FN0
13383-37FE0
13383-37FM0
13383-37FD0
13383-37FL0
3 Adjustment of intermediate system
13383-37FC0
13383-37FK0
13383-37FB0
13383-37FJ0
13383-37FA0
13383-37FH0
Monitor the air/fuel mixture condition and adjust the
intermediate system by changing the needle clip
position.
4 Final adjustment of slow system
After a proper standard setting has been obtained
by the procedure 1 through 3, fine tune the carbu-
retor according to the actual race conditions.
1) Adjust the air/fuel mixture by turning the air
2) If the mixture can not be adjusted by the air
5 Final adjustment of intermediate system
Fine tune the intermediate system by changing the
needle type and clip position.
adjusting the intermediate system.
Ex. Main jet #172
If air/fuel mixture is rich, replace it with
#170 main jet. If air/fuel mixture is lean,
replace it with #175 main jet.
1
2
3
4
5
screw within 1/2 – 2 turns out.
1/2 turn out
3/4 turn out
1 turn out
.................STD
1 and 1/4 turns out
1 and 1/2 turns out
1 and 3/4 turns out
2 turns out
screw within 1/2 – 2 turns out range, readjust
the slow system 1.
Lean
STD
Rich