Yamaha XT250X Service Manual page 168

Valve spring free length
Inner spring
Free length (intake)
36.17 mm (1.42 in)
Free length (exhaust)
36.17 mm (1.42 in)
Outer spring
Free length (intake)
36.63 mm (1.44 in)
Free length (exhaust)
36.63 mm (1.44 in)
2. Measure:
Compressed valve spring force "1"
G
Out of specification → Replace the valve
spring.
a. Compressed valve spring force
b. Installed length
VALVES AND VALVE SPRINGS
Inner spring
Installed
force (intake)
75.00–91.70 N (16.86–20.61 lbf)
(7.65–9.35 kgf)
Installed length (intake)
30.50 mm (1.20 in)
Installed
force (exhaust)
75.00–91.70 N (16.86–20.61 lbf)
(7.65–9.35 kgf)
Installed length (exhaust)
30.50 mm (1.20 in)
Outer spring
Installed
force (intake)
128.50–157.90 N (28.89–35.50
lbf) (13.10–16.10 kgf)
Installed length (intake)
32.00 mm (1.26 in)
Installed
force (exhaust)
128.50–157.90 N (28.89–35.50
lbf) (13.10–16.10 kgf)
Installed length (exhaust)
32.00 mm (1.26 in)
3. Measure:
Valve spring tilt "a"
G
Out of specification → Replace the valve
spring.
Spring tilt limit
Inner spring
Spring tilt (intake)
2.5 °/1.6 mm
Spring tilt (exhaust)
2.5 °/1.6 mm
Outer spring
Spring tilt (intake)
2.5 °/1.6 mm
Spring tilt (exhaust)
2.5 °/1.6 mm
5-22
compression spring
compression spring
compression spring
compression spring