KTM 300 EXC - Carburetor; Carburetor Tuning

22 TECHNICAL DATA
138
22.3 Carburetor
Carburetor type MIKUNI TMX 38
Carburetor identification number TMX 38 86
Needle position 3rd position from top
Jet needle 6BFY43-73 (6BFY42-73, 6BFY42-74, 6BFY43-74)
Main jet 470 (460, 480, 490)
Idling jet 35 (32.5/37.5/40)
Choke nozzle 80
Needle jet S-4
Idle air adjusting screw
Open 2 turns
Throttle slide 4
22.3.1 Carburetor tuning
MIKUNI TMX 38
ASL TEMP
−20 … −7 °C
(−4 … 19 °F)
−6 … 5 °C
(21 …
41 °F)
6 … 15 °C
(43 …
59 °F)
16 … 24 °C
(61 …
75 °F)
25 … 36 °C
(77 …
97 °F)
37 … 49 °C
(99 …
120 °F)
2,301 …
3,000 m
(7,549 …
9,843 ft)
ASO
IJ
NDL
POS
MJ
2.5
32.5
43-73
3
470
2.5
30
43-73
3
460
2
32.5
42-73
3
460
2
30
42-73
3
450
2
30
43-73
2
450
1,501 …
2,300 m
(4,925 …
7,546 ft)
ASO
IJ
NDL
POS
MJ
2
35
43-73
3
470
2.5
32.5
43-73
3
470
2.5
30
43-73
3
460
2
32.5
42-73
3
460
2
30
42-73
3
450
2
30
43-73
2
450
751 …
1,500 m
(2,464 …
4,921 ft)
ASO
IJ
NDL
POS
MJ
2
35
43-73
3
480
2
35
43-73
3
470
2.5
32.5
43-73
3
470
2.5
30
43-73
3
460
2
32.5
42-73
3
460
2
30
42-73
3
450
301 …
750 m
(988 …
2,461 ft)
ASO
IJ
NDL
POS
MJ
2
37.5
43-73
3
490
2
35
43-73
3
480
2
35
43‑73
3
470
2.5
32.5
43-73
3
470
2.5
30
43-73
3
460
2
32.5
42-73
3
460
0 …
300 m (0
… 984 ft)
ASO
IJ
NDL
POS
MJ
2
40
43-73
3
500
2
35
43-73
3
480
2
35
43-73
3
470
2.5
32.5
43-73
3
470
2.5
30
43-73
3
460
2
32.5
42-73
3
460
ASL Sea level
TEMP Temperature
ASO Idle air adjusting screw open
IJ Idling jet
NDL Needle
POS Needle position from top