Yamaha YZ450F Owner's Service Manual page 35

Stem-to-guide clearance (IN)
Stem-to-guide clearance (EX)
Stem runout limit
Valve seat width (IN)
Valve seat width (EX)
Valve spring:
Free length (IN)
Free length (EX)
Set length (valve closed) (IN)
Set length (valve closed) (EX)
Compressed force (installed) (IN)
Compressed force (installed) (EX)
Tilt limit* (IN)
Tilt limit* (EX)
Direction of winding (top view) (IN)
Direction of winding (top view) (EX)
Item
MAINTENANCE SPECIFICATIONS
Standard
0.010–0.037 mm (0.0004–0.0015 in)
0.020–0.047 mm (0.0008–0.0019 in)
----
0.9–1.1 mm (0.0354–0.0433 in)
0.9–1.1 mm (0.0354–0.0433 in)
40.76 mm (1.60 in)
37.01mm (1.46 in)
34.78 mm (1.37 in)
30.83 mm (1.21 in)
178–204 N at 34.78 mm (18.2–20.8 kg at
34.78 mm, 40.01–45.86 lb at 1.37 in)
124–142 N at 30.83 mm (12.6–14.5 kg at
30.83 mm, 27.88–31.92 lb at 1.21 in)
----
----
Clockwise
Clockwise
2-5
Limit
0.08 mm (0.003
in)
0.10 mm (0.004
in)
0.01 mm
(0.0004 in)
1.6 mm (0.0630
in)
1.6 mm (0.0630
in)
39.76 mm (1.57
in)
36.01 mm (1.42
in)
----
----
----
----
2.5°/1.8 mm
(2.5°/0.071 in)
2.5°/1.6 mm
(2.5°/0.063 in)
----
----