CYLINDER HEAD
5-24
EAS30276
REMOVING THE CYLINDER HEAD
1. Remove:
• Cylinder head bolt (M6) (
×
2)
• Cylinder head bolt (M10) (
×
6)
TIP
• Loosen the bolts in the proper sequence as
shown.
• Loosen each bolt 1/2 of a turn at a time. After
all of the bolts are fully loosened, remove them.
• M6
×
105 mm: “1”, “2”
• M10
×
142 mm: “3”–“8”
EAS30278
CHECKING THE TIMING CHAIN GUIDE
(EXHAUST SIDE)
1. Check:
• Timing chain guide (exhaust side)
Damage/wear
→
Replace.
EAS30277
CHECKING THE CYLINDER HEAD
1. Eliminate:
• Combustion chamber carbon deposits
(with a rounded scraper)
TIP
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.
• Cylinder head water jacket
Mineral deposits/rust
→
Eliminate.
3. Measure:
• Cylinder head warpage
Out of specification
→
Resurface the cylinder
head.
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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 cylinder
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.
TIP
To ensure an even surface, rotate the cylinder
head several times.
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EAS30282
INSTALLING THE CYLINDER HEAD
1. Install:
• Bushings “1”
• Engine mounting bolt caps “2”
TIP
• Make sure that the edge “a” of each bushing is
aligned with the edge “b” of the frame as shown
in the illustration.
×2
×6
1
2
5
3
6
4
7
8
FWD
Warpage limit
0.05 mm (0.0020 in)
2
1
Summary of Contents for YZF-R25
Page 1: ......
Page 2: ......
Page 3: ......
Page 6: ......
Page 8: ......
Page 25: ...BASIC SERVICE INFORMATION 1 16 ...
Page 32: ...SPECIAL TOOLS 1 23 ...
Page 49: ...TIGHTENING TORQUES 2 16 2 6 8 5 4 1 2 6 3 7 2 10 9 A ...
Page 66: ...COOLING SYSTEM DIAGRAMS 2 33 EAS20020 COOLING SYSTEM DIAGRAMS 1 2 3 1 5 4 4 ...
Page 99: ......
Page 128: ...PERIODIC MAINTENANCE 3 29 ...
Page 146: ...GENERAL CHASSIS 5 4 15 1 b b a a 2 ...
Page 200: ...FRONT FORK 4 69 2 b a 1 ...
Page 209: ...SWINGARM AND REAR SHOCK ABSORBER ASSEMBLY 4 78 2 1 1 1 a A B ...
Page 214: ...CHAIN DRIVE 4 83 ...
Page 256: ...CYLINDER AND PISTONS 5 39 1 ...
Page 310: ...TRANSMISSION 5 93 ...
Page 322: ...WATER PUMP 6 11 ...
Page 336: ...THROTTLE BODIES 7 13 c 1 cylinder d 2 cylinder A Left B Right b a d c A B b 1 ...
Page 337: ...THROTTLE BODIES 7 14 ...
Page 338: ...AIR INDUCTION SYSTEM 7 15 EAS20071 AIR INDUCTION SYSTEM 1 2 3 4 5 1 2 ...
Page 342: ...AIR INDUCTION SYSTEM 7 19 ...
Page 345: ......
Page 355: ...ELECTRIC STARTING SYSTEM 8 10 ...
Page 359: ...CHARGING SYSTEM 8 14 ...
Page 371: ...SIGNALING SYSTEM 8 26 ...
Page 417: ...FUEL PUMP SYSTEM 8 72 ...
Page 420: ...ELECTRICAL COMPONENTS 8 75 2 3 4 5 12 11 10 9 8 7 1 6 ...
Page 440: ...ELECTRICAL COMPONENTS 8 95 ...
Page 451: ...SELF DIAGNOSTIC FUNCTION AND DIAGNOSTIC CODE TABLE 9 10 ...
Page 453: ......
Page 454: ......