Yamaha FJR1300A(D), Service Manual

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VALVES AND VALVE SPRINGS
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3. Eliminate:
• Carbon deposits
(from the valve face and valve seat)
4. Check:
• Valve face
Pitting/wear
→
Grind the valve face.
• Valve stem end
Mushroom shape or diameter larger than the
body of the valve stem
→
Replace the valve.
5. Measure:
• Valve margin thickness D “a”
Out of specification
→
Replace the valve.
6. Measure:
• Valve stem runout
Out of specification
→
Replace the valve.
TIP
• When installing a new valve, always replace
the valve guide.
• If the valve is removed or replaced, always re-
place the valve stem seal.
EAS24300
CHECKING THE VALVE SEATS
The following procedure applies to all of the
valves and valve seats.
1. Eliminate:
• Carbon deposits
(from the valve face and valve seat)
2. Check:
• Valve seat
Pitting/wear
→
Replace the cylinder head.
3. Measure:
• Valve seat width C “a”
Out of specification
→
Replace the cylinder
head.
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a. Apply Mechanic’s blueing dye (Dykem) “b”
onto the valve face.
Valve guide remover (ø5)
90890-04097
Valve guide remover (5.0 mm)
YM-04097
Valve guide installer (ø5)
90890-04098
Valve guide installer (5.0 mm)
YM-04098
Valve guide reamer (ø5)
90890-04099
Valve guide reamer (5.0 mm)
YM-04099
Valve margin thickness D (intake)
0.80–1.20 mm (0.0315–0.0472 in)
Valve margin thickness D (ex-
haust)
0.50–0.90 mm (0.0197–0.0354 in)
Valve stem runout
0.010 mm (0.0004 in)
Valve seat width C (intake)
0.90–1.10 mm (0.0354–0.0433 in)
Valve seat width C (exhaust)
0.90–1.10 mm (0.0354–0.0433 in)