Installing The Valves - Yamaha 2009 YFM25RY Service Manual

Inner spring
Spring tilt (intake)
2.5 °/1.60 mm (2.5 °/0.063 in)
Spring tilt (exhaust)
2.5 °/1.60 mm (2.5 °/0.063 in)
Outer spring
Spring tilt (intake)
2.5 °/1.60 mm (2.5 °/0.063 in)
Spring tilt (exhaust)
2.5 °/1.60 mm (2.5 °/0.063 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)
2. Lubricate:
• Valve stem
• Valve stem seal
(with the recommended lubricant)
Recommended lubricant
Molybdenum disulfide oil
3. Install:
• Valve spring seat "1"
• Valve stem seal "2"
• Valve "3"
• Inner valve spring "4"
New
5-22
VALVES AND VALVE SPRINGS
• Outer valve spring "5"
• Upper spring seat "6"
(into the cylinder head)
TIP
Install the valve springs with the larger pitch "a"
facing up.
a. Larger pitch
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".
Valve spring compressor
90890-04019
YM-04019
Valve spring compressor
attachment
90890-01243
Valve spring compressor
adapter (26 mm)
YM-01253-1