Installing The Valves - Yamaha SR400 2014 Service Manual

Inner spring
Installed compression spring
force (intake)
119.64 N (12.20 kgf, 26.90 lbf)
Installed compression spring
force (exhaust)
119.64 N (12.20 kgf, 26.90 lbf)
Installed length (intake)
38.00 mm (1.50 in)
Installed length (exhaust)
38.00 mm (1.50 in)
Outer spring
Installed compression spring
force (intake)
160.83 N (16.40 kgf, 36.15 lbf)
Installed compression spring
force (exhaust)
160.83 N (16.40 kgf, 36.15 lbf)
Installed length (intake)
40.00 mm (1.57 in)
Installed length (exhaust)
40.00 mm (1.57 in)
3. Measure:
• Valve spring tilt "a"
Out of specification  Replace the valve
spring.
Inner spring
Spring tilt (intake)
1.9 mm (0.07 in)
Spring tilt (exhaust)
1.9 mm (0.07 in)
Outer spring
Spring tilt (intake)
1.9 mm (0.07 in)
Spring tilt (exhaust)
1.9 mm (0.07 in)
EAS24340

INSTALLING THE VALVES

The following procedure applies to all of the
valves and related components.
1. Deburr:
• Valve stem end
(with an oil stone)
VALVES AND VALVE SPRINGS
2. Lubricate:
• Valve stem "1"
• Valve stem seal "2"
(with the recommended lubricant)
Recommended lubricant
Molybdenum disulfide oil
2
1
3. Install:
• Valve spring seat "1"
• Valve stem seal "2"
• Valve "3"
• Inner valve spring "4"
• Outer valve spring "5"
• Valve spring retainer "6"
(into the cylinder head)
TIP
• Make sure each valve is installed in its original
place. Refer to the following embossed marks.
Intake valve: "2J2"
Exhaust valve: "5A8"
• Install the valve springs with the larger pitch "a"
facing up.
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