Yamaha F15A, Service Manual

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SPEC
MAINTENANCE SPECIFICATIONS (F15A)
2-4
E
Model
Item Unit
F15AMH F15AEH F15AE
F15MHX F15EHX —
Seat width (C) mm (in) 0.6 ~ 0.8 (0.02 ~ 0.03)
Margin thickness (D)
Intake mm (in) 0.50 ~ 0.90 (0.020 ~ 0.035)
Exhaust mm (in) 0.50 ~ 0.90 (0.020 ~ 0.035)
Stem outside diameter
Intake mm (in) 5.475 ~ 5.490 (0.2155 ~ 0.2161)
Exhaust mm (in) 5.460 ~ 5.475 (0.2150 ~ 0.2156)
Guide inside diameter mm (in) 5.500 ~ 5.512 (0.2165 ~ 0.2170)
Stem-to-guide clearance
Intake mm (in) 0.010 ~ 0.037 (0.0004 ~ 0.0015)
Exhaust mm (in) 0.025 ~ 0.052 (0.0010 ~ 0.0020)
Stem runout limit mm (in) 0.016 (0.0006)
VALVE SPRING
Free length mm (in) 34.4 (1.35)
Free length limit mm (in) 32.7 (1.29)
Set length mm/kg (in/lb) 25.4/11.0 (1.00/24.2)
Tilt limit mm (in) 1.5 (0.06)
PISTON
Piston-to-cylinder clearance mm (in) 0.035 ~ 0.065 (0.0014 ~ 0.0026)
Piston diameter (D)
Standard mm (in) 58.950 ~ 58.965 (2.3206 ~ 2.3215)
Measuring point (H) mm (in) 5 (0.20)
Pin boss inside diameter mm (in) 14.004 ~ 14.015 (0.5513 ~ 0.5518)
Oversize piston diameter
1st (except for USA) mm (in) 59.25 (2.333)
2nd mm (in) 59.50 (2.343)
PISTON PIN
Outside diameter mm (in) 13.996 ~ 14.000 (0.5510 ~ 0.5512)
PISTON RINGS
Top ring
Type Barrel
Dimensions (B x T) mm (in) 1.2 x 2.3 (0.05 x 0.09)
End gap (installed) mm (in) 0.15 ~ 0.30 (0.006 ~ 0.012)
Wear limit mm (in) 0.50 (0.020)
Side clearance (installed) mm (in) 0.013 ~ 0.035 (0.0005 ~ 0.0013)
2nd ring
Type Plane
Dimensions (B x T) mm (in) 1.5 x 2.6 (0.06 x 0.10)
End gap (installed) mm (in) 0.30 ~ 0.50 (0.012 ~ 0.020)
Wear limit mm (in) 0.70 (0.028)
Side clearance (installed) mm (in) 0.02~0.04 (0.001 ~ 0.002)
World-
wide
USA/
CANADA