VALVES AND VALVE SPRINGS
5-27
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EASB29B226
CHECKING THE VALVE SPRINGS
1. Measure:
• Valve spring free length “a”
Out of specification
Replace the valve
spring.
2. Measure:
• Valve spring tilt “a”
Out of specification
Replace the valve
spring.
EASB29B227
CHECKING THE VALVE LIFTERS
1. Check:
• Valve lifter
Damage/scratches
Replace the valve lift-
ers and cylinder head.
EASB29B228
INSTALLING THE VALVES
1. Clean:
• Valve stem end
2. Lubricate:
• Valve stem “1”
• Valve stem seal “2”
Free length (intake)
39.03 mm (1.54 in)
Limit
37.08 mm (1.46 in)
Free length (exhaust)
35.59 mm (1.40 in)
Limit
33.81 mm (1.33 in)
Spring tilt (intake)
1.7 mm (0.07 in)
Spring tilt (exhaust)
1.6 mm (0.06 in)
Recommended lubricant
Molybdenum disulfide oil
Summary of Contents for YZ 2018 Series
Page 6: ...EASB916006 YAMAHA MOTOR CORPORATION U S A YZ MOTORCYCLE LIMITED WARRANTY...
Page 10: ......
Page 40: ...MOTORCYCLE CARE AND STORAGE 1 28...
Page 64: ...LUBRICATION SYSTEM CHART AND DIAGRAMS 2 23...
Page 66: ...LUBRICATION SYSTEM CHART AND DIAGRAMS 2 25...
Page 68: ...LUBRICATION SYSTEM CHART AND DIAGRAMS 2 27...
Page 70: ...CABLE ROUTING DIAGRAM 2 29 EASB29B065 CABLE ROUTING DIAGRAM...
Page 72: ...CABLE ROUTING DIAGRAM 2 31...
Page 74: ...CABLE ROUTING DIAGRAM 2 33...
Page 76: ...CABLE ROUTING DIAGRAM 2 35...
Page 78: ...CABLE ROUTING DIAGRAM 2 37...
Page 80: ...CABLE ROUTING DIAGRAM 2 39...
Page 82: ...CABLE ROUTING DIAGRAM 2 41...
Page 84: ...CABLE ROUTING DIAGRAM 2 43...
Page 255: ...OIL PUMP AND BALANCER GEAR 5 58 a 2 10 b 2 9 1 b 5 3 a 4 10 5 9 3 E c d 6 7 8 8 b 6...
Page 276: ...TRANSMISSION 5 79...
Page 290: ...FUEL TANK 7 5 A Left B Right 1 1 A 0 mm 0 in B 1 1 15 mm 0 59 in...
Page 296: ...THROTTLE BODY 7 11...
Page 299: ......
Page 313: ...CHARGING SYSTEM 8 14...
Page 321: ...COOLING SYSTEM For JPN 8 22...
Page 351: ...FUEL PUMP SYSTEM 8 52 EASB29B345...
Page 352: ...ELECTRICAL COMPONENTS 8 53 ELECTRICAL COMPONENTS EASB29B346 9 10 11 1 3 2 4 5 6 7 8...
Page 354: ...ELECTRICAL COMPONENTS 8 55 11 10 9 2 3 1 6 7 8 4 5...
Page 356: ...ELECTRICAL COMPONENTS 8 57 EASB29B347 CHECKING THE SWITCHES 4 1 3 2 B B Sb B B B B B B B B...
Page 372: ...ELECTRICAL COMPONENTS 8 73 c Measure the fuel injector resistance...