Yamaha YZ 2019 Series Owner's Service Manual page 44

Camshaft-journal-to-camshaft-cap clearance
Limit
Camshaft lobe dimensions
Lobe height (Intake)
Limit
Lobe height (Exhaust)
Limit
Camshaft runout limit
Valve, valve seat, valve guide
Valve clearance (cold)
Intake
Exhaust
Valve dimensions
Valve seat contact width (intake)
Limit
Valve seat contact width (exhaust)
Limit
Valve stem diameter (intake)
Limit
Valve stem diameter (exhaust)
Limit
Valve guide inside diameter (intake)
Valve guide inside diameter (exhaust)
Valve-stem-to-valve-guide clearance (in-
take)
Limit
Valve-stem-to-valve-guide clearance (ex-
haust)
Limit
Valve stem runout
Valve spring
Free length (intake)
Limit
Free length (exhaust)
Limit
Cylinder
Bore
Wear limit
Piston
Piston-to-cylinder clearance
Diameter
Measuring point (from piston skirt bottom)
Piston pin bore inside diameter
Limit
Piston pin outside diameter
Limit
Piston-pin-to-piston-pin-bore clearance
Piston ring
Top ring
End gap (installed)
ENGINE SPECIFICATIONS
0.028–0.062 mm (0.0011–0.0024 in)
0.080 mm (0.0032 in)
31.830–31.930 mm (1.2531–1.2571 in)
31.730 mm (1.2492 in)
33.870–33.970 mm (1.3335–1.3374 in)
33.770 mm (1.3295 in)
0.030 mm (0.0012 in)
0.12–0.19 mm (0.0047–0.0075 in)
0.17–0.24 mm (0.0067–0.0094 in)
0.90–1.10 mm (0.0354–0.0433 in)
1.6 mm (0.06 in)
0.90–1.10 mm (0.0354–0.0433 in)
1.6 mm (0.06 in)
4.975–4.990 mm (0.1959–0.1965 in)
4.945 mm (0.1947 in)
4.460–4.475 mm (0.1756–0.1762 in)
4.430 mm (0.1744 in)
5.000–5.012 mm (0.1969–0.1973 in)
4.500–4.512 mm (0.1772–0.1776 in)
0.010–0.037 mm (0.0004–0.0015 in)
0.080 mm (0.0032 in)
0.025–0.052 mm (0.0010–0.0020 in)
0.100 mm (0.0039 in)
0.010 mm (0.0004 in)
39.03 mm (1.54 in)
37.08 mm (1.46 in)
35.59 mm (1.40 in)
33.81 mm (1.33 in)
77.000–77.010 mm (3.0315–3.0319 in)
77.060 mm (3.0339 in)
0.030–0.055 mm (0.0012–0.0022 in)
76.955–76.970 mm (3.0297–3.0303 in)
4.0 mm (0.16 in)
16.002–16.013 mm (0.6300–0.6304 in)
16.043 mm (0.6316 in)
15.991–16.000 mm (0.6296–0.6299 in)
15.971 mm (0.6288 in)
0.002–0.022 mm (0.0001–0.0009 in)
0.15–0.25 mm (0.0059–0.0098 in)
2-3