Suzuki VZ800 Service Manual page 77

• Pull out the valve 5 from the other side.
• Remove the valve stem seal 6 and valve spring seat 7.
NOTE:
Removal of valves completes ordinary disassembling work. If
valve guides have to be removed for replacement after inspect-
ing related parts, carry out the steps shown in valve guide ser-
vicing. (3-32)
CYLINDER HEAD DISTORTION
• Decarbonize the combustion chambers.
Check the gasketed surface of the cylinder head for distortion
with a straightedge and thickness gauge, taking a clearance
reading at several places indicated. If the largest reading at any
position of the straightedge exceeds the limit, replace the cylin-
der head.
 Cylinder head distortion
Service Limit: 0.05 mm (0.002 in)
 09900-20803: Thickness gauge
VALVE FACE WEAR
Visually inspect each valve for wear of its seating face. Replace
any valve with an abnormally worn face.
The thickness T decreases as the wear of the face advances.
Measure the thickness and, if the thickness is found to have
been reduced to the limit, replace it.
 Valve head thickness
Service Limit T: 0.5 mm (0.02 in)
 09900-20102: Vernier calipers
VALVE STEM RUNOUT
Support the valve with "V" blocks, as shown, and check its
runout with a dial gauge.
The valve must be replaced if the runout exceeds the limit.
 Valve stem runout
Service Limit: 0.05 mm (0.002 in)
 09900-20701: Magnetic stand
09900-20607: Dial gauge (1/100 mm)
09900-21304: V-block
ENGINE 3-31