Yamaha MX400 - Page 15

2-6
SPEC
Model name:
MZ400 MX400
Model code number:
7HSB 7HSJ
Valve spring: mm (in)
Free length IN
36.2 (1.4252)
EX
36.2 (1.4252)
<Limit> IN
34.39 (1.3539)
EX
34.39 (1.3539)
Installed length IN
29 (1.1417)
EX
29 (1.1417)
Installed compression spring force
IN N (kgf, lbf) 91.20–104.93 (9.12–10.49, 20.50–23.59)
EX N (kgf, lbf)
91.20–104.93 (9.12–10.49, 20.50–23.59)
Tilt limit mm (in)
1.7 (0.0669)
Carburetor: mm (in)
Type/manufacture
RUIXNG
I.D. mark
7HP-E4301-**
Bore size
ø26
Main jet
1.23 (0.050) 1.27 (0.050)
Main air jet
1.4 (0.055)
Pilot air jet
1.2 (0.045)
Pilot outlet
1.0 (0.039)
Valve seat size
1.8 (0.070)
Pilot jet
0.54 (0.02) 0.55 (0.02)
Pilot screw
1 3/4 turns out
Throttle valve
13° 14°
Float height “H”
14.9 (0.59)
Governor arm:
Tension spring attach hole
3 1
Engine speed: r/min
3700–3800 3750–3850
High engine speed
Low engine speed 1900–2100
1
2
3
4
5
6
7
8
9
MAINTENANCE SPECIFICATIONS