Crankcase Assembly - Yamaha F25 Service Manual

SPEC

Crankcase assembly

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
Crankcase
Crankshaft journal oil
clearance
1-17
Specification
Unit
mm (in)
mm (in)
mm (in)
mm (in)
mm (in)
mm (in)
mm (in)
mm (in)
mm (in)
mm (in)
mm (in)
mm (in)
mm (in)
mm (in)
mm (in)
mm (in)
mm (in)
mm (in)
mm (in)
mm (in)
mm (in)
mm (in)
mm (in)
mm (in)
mm (in)
mm (in)
mm (in)
mm (in)
mm (in)
mm (in)
mm (in)
mm (in)
mm (in)
Model
F25MHA
65.000–65.015 (2.5591–2.5596)
64.950–64.965 (2.5571–2.5577)
5.0 (0.20)
0.035–0.065 (0.0014–0.0026)
1.210–1.230 (0.0476–0.0484)
1.510–1.530 (0.0594–0.0602)
2.520–2.540 (0.0992–0.1000)
15.974–15.985 (0.6289–0.6293)
15.965–15.970 (0.6285–0.6287)
65.200–65.215 (2.5669–2.5675)
65.450–65.465 (2.5768–2.5774)
20.0 (0.79)
Barrel
1.170–1.190 (0.0461–0.0469)
2.300–2.500 (0.0906–0.0984)
0.150–0.300 (0.0059–0.0118)
0.020–0.060 (0.0008–0.0024)
Taper
1.470–1.490 (0.0579–0.0587)
2.600–2.800 (0.1024–0.1102)
0.300–0.500 (0.0118–0.0197)
0.020–0.060 (0.0008–0.0024)
2.360–2.480 (0.0929–0.0976)
2.750 (0.1083)
0.200–0.700 (0.0079–0.0276)
0.040–0.180 (0.0016–0.0071)
15.985–15.998 (0.6293–0.6298)
36.000–36.024 (1.4173–1.4183)
0.050–0.220 (0.0020–0.0087)
0.016–0.040 (0.0006–0.0016)
42.986–43.000 (1.6924–1.6929)
32.993–33.000 (1.2989–1.2992)
0.035 (0.0014)
21.000–21.070 (0.8268–0.8295)
0.012–0.036 (0.0005–0.0014)
F25EHA