Yamaha F25 Service Manual page 36

Item
Cylinder
Bore
Piston
Diameter
Measuring point
Piston clearance
Ring groove (Top)
Ring groove (2nd)
Ring groove (Oil)
Pin boss inside diameter
Pin outside diameter
Oversize diameter
1st
2nd
Piston ring
End gap measuring point
Top ring
Type
Dimension height (B)
Dimension width (T)
End gap (*1)
Side clearance
2nd ring
Type
Dimension height (B)
Dimension width (T)
End gap (*1)
Side clearance
Oil ring
Dimension height (B)
Dimension width (T)
End gap (*1)
Side clearance
Connecting rod
Small end inside diameter
Big end inside diameter
Big end side clearance
Crankpin oil clearance
Crankshaft
Journal diameter
Crankpin diameter
Runout
Crankpin width
Unit
F25EA
mm (in) 65.000–65.015 (2.5591–2.5596)
mm (in) 64.950–64.965 (2.5571–2.5577)
mm (in)
mm (in) 0.035–0.065 (0.0014–0.0026)
mm (in) 1.210–1.230 (0.0476–0.0484)
mm (in) 1.510–1.530 (0.0594–0.0602)
mm (in) 2.520–2.540 (0.0992–0.1000)
mm (in) 15.974–15.985 (0.6289–0.6293)
mm (in) 15.965–15.970 (0.6285–0.6287)
mm (in) 65.200–65.215 (2.5669–2.5675)
mm (in) 65.450–65.465 (2.5768–2.5774)
mm (in)
mm (in) 1.170–1.190 (0.0461–0.0469)
mm (in) 2.300–2.500 (0.0906–0.0984)
mm (in) 0.150–0.300 (0.0059–0.0118)
mm (in) 0.020–0.060 (0.0008–0.0024)
mm (in) 1.470–1.490 (0.0579–0.0587)
mm (in) 2.600–2.800 (0.1024–0.1102)
mm (in) 0.300–0.500 (0.0118–0.0197)
mm (in) 0.020–0.060 (0.0008–0.0024)
mm (in) 2.360–2.480 (0.0929–0.0976)
mm (in)
mm (in) 0.200–0.700 (0.0079–0.0276)
mm (in) 0.040–0.180 (0.0016–0.0071)
mm (in) 15.985–15.998 (0.6293–0.6298)
mm (in) 36.000–36.024 (1.4173–1.4183)
mm (in) 0.050–0.220 (0.0020–0.0087)
mm (in) 0.016–0.040 (0.0006–0.0016)
mm (in) 42.986–43.000 (1.6924–1.6929)
mm (in) 32.993–33.000 (1.2989–1.2992)
mm (in)
mm (in) 21.000–21.070 (0.8268–0.8295)
Power unit technical data
Model
F25A T25A
5.0 (0.20)
20.0 (0.79)
Barrel
Taper
2.750 (0.1083)
0.035 (0.0014)
1
1-18