Yamaha YZF-R25, Service Manual

Page: 235 / 456

CAMSHAFTS
5-18
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4. Install:
• Dwell pins
• Exhaust camshaft cap “1”
• Intake camshaft cap “2”
TIP
• Make sure each camshaft cap is installed in its
original place. Refer to the identification marks
as follows:
“EX”: Exhaust camshaft cap mark “a”
“IN”: Intake camshaft cap mark “b”
• Make sure the arrow mark “c” on each cam-
shaft cap points toward the right side of the en-
gine.
5. Tighten:
• Camshaft cap bolts
NOTICE
ECA20930
• Lubricate the camshaft cap bolts with the
engine oil.
• The camshaft cap bolts must be tightened
evenly or damage to the cylinder head,
camshaft caps, and camshafts will result.
• Do not turn the crankshaft when installing
the camshaft to avoid damage or improper
valve timing.
TIP
Tighten the camshaft cap bolts in the tightening
sequence as shown.
6. Install:
• Timing chain tensioner gasket
• Timing chain tensioner
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a. While lightly pressing the timing chain ten-
sioner rod by hand, turn the timing chain ten-
sioner rod fully counterclockwise with a
hexagon wrench “1” (Part No.: 1WS-12228-
00).
b. Install a new timing chain tensioner gasket,
the timing chain tensioner “3”, and the timing
chain tensioner bolts “4” on the cylinder head.
TIP
Be sure to install the timing chain tensioner gas-
ket so that the portion “a” of the gasket is pro-
truding from the lower inner side of the timing
chain tensioner.
T
R
.
.
Camshaft cap bolt
10 Nm (1.0 m·kgf, 7.2 ft·lbf)
e
d
4
2
1
1
2
c
a
b
6
4
3
5
1
2
6
4
3
5
1
2
New
1
4
3
a