Yamaha WR426F(P), Owner'S Service Manual

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SPEC
MAINTENANCE SPECIFICATIONS (WR400F)
Cam chain:
Cam chain type/No. of links 92RH2010-120MPX/120 ----
Cam chain adjustment method Automatic ----
Valve, valve seat, valve guide:
Valve clearance (cold) IN 0.10 ~ 0.15 mm
(0.0039 ~ 0.0059 in) ----
EX 0.20 ~ 0.25 mm
(0.0079 ~ 0.0098 in) ----
Valve dimensions:
“A” head diameter IN 26.9 ~ 27.1 mm
(1.0591 ~ 1.0669 in) ----
EX 27.9 ~ 28.1 mm
(1.0984 ~ 1.1063 in) ----
“B” face width IN 2.26 mm (0.089 in) ----
EX 2.26 mm (0.089 in) ----
“C” seat width IN 0.9 ~ 1.1 mm
(0.0354 ~ 0.0433 in) 1.6 mm
(0.0630 in)
EX 0.9 ~ 1.1 mm
(0.0354 ~ 0.0433 in) 1.6 mm
(0.0630 in)
“D” margin thickness IN 1 mm (0.0394 in) 0.85 mm
(0.033 in)
EX 1 mm (0.0394 in) 0.85 mm
(0.033 in)
Stem outside diameter IN 4.475 ~ 4.490 mm
(0.1762 ~ 0.1768 in) 4.445 mm
(0.1750 in)
EX 4.965 ~ 4.980 mm
(0.1955 ~ 0.1961 in) 4.935 mm
(0.1943 in)
Guide inside diameter IN 4.500 ~ 4.512 mm
(0.1772 ~ 0.1776 in) 4.550 mm
(0.1791 in)
EX 5.000 ~ 5.012 mm
(0.1969 ~ 0.1973 in) 5.050 mm
(0.1988 in)
Stem-to-guide clearance IN 0.010 ~ 0.037 mm
(0.0004 ~ 0.0015 in) 0.08 mm
(0.003 in)
EX 0.020 ~ 0.047 mm
(0.0008 ~ 0.0019 in) 0.10 mm
(0.004 in)
Stem runout limit ---- 0.01 mm
(0.0004 in)
Item Standard Limit
Head Diameter
B
Face Width
C
Seat Width
D
Margin Thickness
A