Yamaha MBK MW125 2014, Service Manual

Page: 33 / 380

ENGINE SPECIFICATIONS
2-4
Valve spring
Free length (intake) 33.75 mm (1.33 in)
Limit 33.40 mm (1.31 in)
Free length (exhaust) 33.75 mm (1.33 in)
Limit 33.40 mm (1.31 in)
Installed length (intake) 26.80 mm (1.06 in)
Installed length (exhaust) 26.80 mm (1.06 in)
Installed compression spring force (intake) 132.20–152.20 N (13.48–15.52 kgf, 29.72–
34.21 lbf)
Installed compression spring force (exhaust) 132.20–152.20 N (13.48–15.52 kgf, 29.72–
34.21 lbf)
Spring tilt (intake) 1.5 mm (0.06 in)
Spring tilt (exhaust) 1.5 mm (0.06 in)
Winding direction (intake) Clockwise
Winding direction (exhaust) Clockwise
Cylinder
Bore 52.400–52.425 mm (2.0630–2.0640 in)
Taper limit 0.050 mm (0.0020 in)
Out of round limit 0.050 mm (0.0020 in)
Warp limit 0.03 mm (0.0012 in)
Piston
Piston-to-cylinder clearance 0.031–0.048 mm (0.0012–0.0019 in)
Diameter 52.362–52.385 mm (2.0615–2.0624 in)
Measuring point (from piston skirt bottom) 7.0 mm (0.28 in)
Piston pin bore inside diameter 14.002–14.013 mm (0.5513–0.5517 in)
Limit 14.043 mm (0.5529 in)
Piston pin outside diameter 13.995–14.000 mm (0.5510–0.5512 in)
Limit 13.975 mm (0.5502 in)
Piston-pin-to-piston-pin-bore clearance 0.002–0.018 mm (0.0001–0.0007 in)
Piston ring
Top ring
Ring type Barrel
End gap (installed) 0.07–0.17 mm (0.0028–0.0067 in)
Limit 0.42 mm (0.0165 in)
Ring side clearance 0.030–0.065 mm (0.0012–0.0026 in)
Limit 0.115 mm (0.0045 in)
2nd ring
Ring type Taper
End gap (installed) 0.35–0.50 mm (0.0138–0.0197 in)
Limit 0.85 mm (0.0335 in)
Ring side clearance 0.020–0.055 mm (0.0008–0.0022 in)
Limit 0.115 mm (0.0045 in)
Oil ring
End gap (installed) 0.20–0.70 mm (0.0079–0.0276 in)
Crankshaft
Crank assembly width 45.45–45.50 mm (1.789–1.791 in)
Runout limit 0.030 mm (0.0012 in)
Big end side clearance 0.110–0.410 mm (0.0043–0.0161 in)