Yamaha 2011 WR450FA, Руководство по эксплуатации для владельца

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VALVES AND VALVE SPRINGS
h. Press the valve through the valve
guide and onto the valve seat to
make a clear pattern.
i. Measure the valve seat width
again. If the valve seat width is out
of specification, reface and relap
the valve seat.
CHECKING THE VALVE SPRINGS
1. Measure:
• Valve spring free length "a"
Out of specification
→
Replace.
2. Measure:
• Compressed spring force "a"
Out of specification
→
Replace.
b. Installed length
3. Measure:
• Spring tilt "a"
Out of specification
→
Replace.
CHECKING THE VALVE LIFTERS
1. Inspect:
• Valve lifter
Scratches/damage
→
Replace
both lifters and cylinder head.
INSTALLING THE VALVES
1. Apply:
• Molybdenum disulfide oil
Onto the valve stem and valve
stem seal.
2. Install:
• Valves "1"
• Valve spring seats "2"
• Valve stem seals "3"
• Valve springs "4"
• Valve spring retainers "5"
• Make sure that each valve is in-
stalled in its original place, also re-
ferring to the painted color as
follows.
Intake (middle) "a": blue
Intake (right/left) "b": gray
Exhaust "c": brown
• Install the valve springs with the
larger pitch "d" facing upward.
e. Smaller pitch
3. Install:
• Valve cotters
While compressing the valve spring
with a valve spring compressor "1" in-
stall the valve cotters.
4. To secure the valve cotters onto
the valve stem, lightly tap the
valve tip with a piece of wood.
Hitting the valve tip with excessive
force could damage the valve.
5. Install:
• Adjusting pad "1"
• Valve lifter "2"
• Apply the molybdenum disulfide oil
on the valve stem end.
• Apply the engine oil on the valve lift-
ers.
• Valve lifter must turn smoothly
when rotated with a finger.
• Be careful to reinstall valve lifters
and pads in their original place.
Free length (valve
spring):
Intake:
39.46 mm (1.55 in)
<Limit>: 38.46 mm
(1.51 in)
Exhaust:
37.61 mm (1.48 in)
<Limit>: 36.61 mm
(1.44 in)
Compressed spring
force:
Intake:
130.2–149.8 N at 27.87
mm (13.28–15.28 kg at
27.87 mm, 29.27–
33.68 lb at 1.10 in)
Exhaust:
123.1–141.7 N at 28.38
mm (12.55–14.45 kg at
28.38 mm, 27.67–
31.85 lb at 1.12 in)
Spring tilt limit:
Intake:
2.5°/1.7 mm (0.067 in)
Exhaust:
2.5°/1.6 mm (0.063 in)
Valve spring compres-
sor:
YM-4019/90890-04019