4-18
VALVES AND VALVE SPRINGS
REMOVING THE VALVE LIFTER
AND VALVE COTTER
1. Remove:
• Valve lifter "1"
• Pad "2"
Identify each lifter "1" and pad "2" po-
sition very carefully so that they can
be reinstalled in their original place.
2. Check:
• Valve sealing
Leakage at the valve seat
→
In-
spect the valve face, valve seat
and valve seat width.
Checking steps:
a. Pour a clean solvent "1" into the
intake and exhaust ports.
b. Check that the valve seals prop-
erly.
There should be no leakage at the
valve seat "2".
3. Remove:
• Valve cotter
Remove the valve cotters by com-
pressing the valve spring with the
valve spring compressor "1" and the
valve spring compressor attachment
"2".
CHECKING THE VALVE
1. Measure:
• Stem-to-guide clearance
Out of specification
→
Replace
the valve guide.
2. Replace:
• Valve guide
Replacement steps:
To ease guide removal, installation
and to maintain correct fit heat the
cylinder head in an over to 100 °C
(212°F).
a. Remove the valve guide using a
valve guide remover "1".
b. Install the new valve guide using a
valve guide remover "1" and valve
guide installer "2".
c. After installing the valve guide,
bore the valve guide using a valve
guide reamer "3" to obtain proper
stem-to-guide clearance.
After replacing the valve guide reface
the valve seat.
Valve spring compres-
sor:
YM-4019/90890-04019
Stem-to-guide clearance = valve
guide inside diameter "a" -
valve stem diameter "b"
Clearance (stem to
guide):
Intake:
0.010–0.037 mm
(0.0004–0.0015 in)
<Limit>:0.08 mm
(0.003 in)
Exhaust:
0.020–0.047 mm
(0.0008–0.0019 in)
<Limit>:0.10 mm
(0.004 in)
Valve guide installation
height "a":
Intake:
15.1–15.5 mm
(0.59–0.61 in)
Exhaust:
12.2–12.6 mm
(0.48–0.50 in)
Valve guide remover &
installer set (ø5.5):
90890-04016
Valve guide remover (5.5
mm):
YM-01122
Valve guide installer (5.5
mm):
YM-04015
Valve guide reamer (5.5
mm):
YM-01196
Содержание YZ450F(B) 2012
Страница 4: ......
Страница 12: ...1 2 LOCATION OF IMPORTANT LABELS EUROPE ...
Страница 13: ...1 3 LOCATION OF IMPORTANT LABELS AUS NZ ZA ...
Страница 48: ...2 18 CABLE ROUTING DIAGRAM CABLE ROUTING DIAGRAM ...
Страница 50: ...2 20 CABLE ROUTING DIAGRAM F F A B D D C C E F F C C D D B A E 100mm ...
Страница 52: ...2 22 CABLE ROUTING DIAGRAM B B F G A A C C D D E E B B G F C C D D E E A A ...
Страница 69: ...3 13 ENGINE INTAKE EXHAUST ...
Страница 87: ...4 6 RADIATOR 11 Pipe 1 O ring 1 1 Order Part name Q ty Remarks ...
Страница 117: ...4 36 OIL PUMP 15 Oil pump drive shaft 1 16 Rotor housing 1 Order Part name Q ty Remarks ...
Страница 168: ...5 29 STEERING 10 Bearing race 2 Refer to removal section Order Part name Q ty Remarks ...
Страница 183: ...6 5 THROTTLE BODY DISASSEMBLING THE THROTTLE BODY Order Part name Q ty Remarks 1 Injector 1 2 Gasket 2 ...
Страница 227: ......
Страница 228: ...PRINTED IN JAPAN E PRINTED ON RECYCLED PAPER ...