CYLINDER HEAD
5-10
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.
NOTE:
To ensure an even surface, rotate the cylinder
head several times.
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EAS5D71031
CHECKING THE CAMSHAFT SPROCKET
AND TIMING CHAIN GUIDE
1. Check:
• Camshaft sprocket
More than 1/4 tooth wear “a”
→
Replace the
camshaft sprocket, timing chain and crank-
shaft as a set.
2. Check:
• Timing chain guide (exhaust side)
Damage/wear
→
Replace.
EAS24200
CHECKING THE TIMING CHAIN TENSIONER
1. Check:
• Timing chain tensioner
Cracks/damage/rough movement
→
Re-
place.
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a. Lightly press the timing chain tensioner rod
into the timing chain tensioner housing by
hand.
NOTE:
While pressing the timing chain tensioner rod,
wind it clockwise with a thin screwdriver “1” until
it stops.
b. Remove the screwdriver and slowly release
the timing chain tensioner rod.
Warpage limit
0.03 mm (0.0012 in)
a. 1/4 tooth
b. Correct
1. Timing chain roller
2. Camshaft sprocket
1
YamahaR125.COM
Summary of Contents for YZF-R125
Page 1: ...5D7 F8197 E0 YAMAHAR125 COM SERVICE MANUAL YZF R125 ...
Page 6: ...YamahaR125 COM ...
Page 8: ...YamahaR125 COM ...
Page 52: ...LUBRICATION SYSTEM CHART AND DIAGRAMS 2 29 1 2 3 4 YamahaR125 COM ...
Page 70: ...CABLE ROUTING 2 47 YamahaR125 COM ...
Page 73: ...YamahaR125 COM ...
Page 102: ...ELECTRICAL SYSTEM 3 29 YamahaR125 COM ...
Page 105: ...YamahaR125 COM ...
Page 172: ...CHAIN DRIVE 4 67 YamahaR125 COM ...
Page 181: ...ENGINE REMOVAL 5 6 2 2 4 1 3 YamahaR125 COM ...
Page 263: ...THROTTLE BODY 7 8 YamahaR125 COM ...
Page 264: ...AIR INDUCTION SYSTEM 7 9 EAS27040 AIR INDUCTION SYSTEM 1 2 3 YamahaR125 COM ...
Page 268: ...AIR INDUCTION SYSTEM 7 13 YamahaR125 COM ...
Page 271: ...YamahaR125 COM ...
Page 283: ...CHARGING SYSTEM 8 12 1 AC magneto 3 Rectifier regulator 4 Main fuse 9 Battery YamahaR125 COM ...
Page 285: ...CHARGING SYSTEM 8 14 YamahaR125 COM ...
Page 295: ...SIGNALING SYSTEM 8 24 YamahaR125 COM ...
Page 299: ...COOLING SYSTEM 8 28 YamahaR125 COM ...
Page 323: ...FUEL INJECTION SYSTEM 8 52 YamahaR125 COM ...
Page 327: ...FUEL PUMP SYSTEM 8 56 YamahaR125 COM ...
Page 353: ...YamahaR125 COM ...
Page 354: ...YamahaR125 COM ...