Removing The Cylinder Head; Checking The Cylinder Head; Installing The Cylinder Head - Yamaha YZFR6X(C) 2008 Service Manual

EAS24120

REMOVING THE CYLINDER HEAD

1. Remove:
• Cylinder head bolts
• Cylinder head nuts
NOTE:
• Loosen the nuts, cap nuts, and bolts in
decreasing numerical order (refer to the
numbers in the illustration).
• Loosen each nut 1/2 of a turn at a time. After
all of the nuts are fully loosened, remove
them.
6 2
8
9
3 1
EAS24160

CHECKING THE CYLINDER HEAD

1. Eliminate:
• Combustion chamber carbon deposits
(with a rounded scraper)
NOTE:
Do not use a sharp instrument to avoid damag-
ing or scratching:
• Spark plug bore threads
• Valve seats
2. Check:
• Cylinder head
Damage/scratches → Replace.
NOTE:
Replace the titanium valves with the cylinder
head.
Refer to "CHECKING THE VALVE SEATS"
on page 5-21.
• Cylinder head water jacket
4 10
12
11
7
5
5-16
CYLINDER HEAD
Mineral deposits/rust → Eliminate.
3. Measure:
• Cylinder head warpage
Out of specification → Resurface the cyl-
inder head.
Warpage limit
0.05 mm (0.0020 in)
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a. Place a straightedge "1" and a thickness
gauge "2" across the cylinder head.
b. Measure the warpage.
c. If the limit is exceeded, resurface the cylin-
der head as follows.
d. Place a 400–600 grit wet sandpaper on the
surface plate and resurface the cylinder
head using a figure-eight sanding pattern.
NOTE:
To ensure an even surface, rotate the cylinder
head several times.
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EAS24240

INSTALLING THE CYLINDER HEAD

1. Install:
• Cylinder head
NOTE:
Pass the timing chain through the timing chain
cavity.
2. Tighten:
• Cylinder head nuts "1"–"7", "10"