Suzuki Wagon R Manual page 2231

6A2-64 ENGINE MECHANICAL (M13 ENGINE)
• Inspect valve stem end face for pitting and wear. If pitting or
wear is found there, valve stem end may be resurfaced, but
not too much to grind off its chamber. When it is worn out too
much that its chamber is gone, replace valve.
Valve head thickness
Measure thickness "a" of valve head. If measured thickness
exceeds limit, replace valve.
Valve head thickness "a" (In and Ex)
Standard: 1.25 – 1.55 mm (0.050 – 0.061 in.)
Limit: 0.9 mm (0.035 in.)
Valve head radial runout
Check each valve for radial runout with a dial gauge and "V"
block. To check runout, rotate valve slowly. If runout exceeds its
limit, replace valve.
Limit on valve head radial runout
0.08 mm (0.003 in.)
Seating contact width
Create contact pattern on each valve in the usual manner, i.e. by
giving uniform coat of marking compound to valve seat and by
rotatingly tapping seat with valve head. Valve lapper (tool used in
valve lapping) must be used.
Pattern produced on seating face of valve must be a continuous
ring without any break, and the width of pattern must be within
specified range.
Standard seating width "a" revealed by contact pattern on
valve face
In and Ex: 1.0 – 1.4 mm (0.0394 - 0.0551 in.)