Checking The Valve Springs; Installing The Valves - Yamaha R15 2022 Service Manual

EAS30286

CHECKING THE VALVE SPRINGS

The following procedure applies to all of the
valve springs.
1. Measure:
• Valve spring free length "a"
Out of specification → Replace the valve
spring.
Free length (intake)
Limit
32.11 mm (1.26 in)
Free length (exhaust)
Limit
32.11 mm (1.26 in)
G088971
EAS30288

INSTALLING THE VALVES

The following procedure applies to all of the
valves and related components.
1. Deburr:
• Valve stem end
(with an oil stone)
G088972
2. Lubricate:
• Valve stem "1"
• Valve stem seal "2"
(with the recommended lubricant)
Recommended lubricant
Molybdenum disulfide oil
Valve stem seal
Engine oil
VALVES AND VALVE SPRINGS
New
3. Install:
• Lower spring seat "1"
• Valve stem seal "2"
• Valve "3"
• Valve spring "4"
• Upper spring seat "5"
(into the cylinder head)
TIP
• Make sure each valve is installed in its original
place.
• Install the valve springs with the larger pitch "a"
facing up.
1
3
b. Smaller pitch
4. Install:
• Valve cotters "1"
TIP
Install the valve cotters by compressing the
valve spring with the valve spring compressor
and the valve spring compressor attachment "2".
5-25
ENG
E
New
5
4
2
New