Suzuki RM-Z250 Owner's Service Manual page 102

6-12 CYLINDER HEAD, CYLINDER AND PISTON
CYLINDER HEAD DISTORTION
• Decarbonize the combustion chamber.
• Check the gasket 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 cylinder head.
" Cylinder head distortion:
Service Limit: 0.05 mm (0.002 in)
# 09900-20803: Thickness gauge
VALVE STEM RUNOUT
• Support the valve using V-blocks and check its runout using
the dial gauge as shown.
• If the runout exceeds the service limit, replace the valve.
Be careful not to damage the valve head and valve
stem when handling it.
" Valve stem runout (IN. & EX.):
Service Limit: 0.05 mm (0.002 in)
# 09900-20607: Dial gauge (1/100, 10 mm)
09900-20701: Magnetic stand
09900-21304: V-block (100 mm)
VALVE HEAD RADIAL RUNOUT
• Place the dial gauge at a right angle to the valve head face
and measure the valve head radial runout.
• If it measures more than the service limit, replace the valve.
Be careful not to damage the valve head and valve
stem when handling it.
" Valve head radial runout (IN. & EX.):
Service Limit: 0.03 mm (0.001 in)
# 09900-20607: Dial gauge (1/100, 10 mm)
09900-20701: Magnetic stand
09900-21304: V-block (100 mm)
VALVE STEM AND VALVE FACE WEAR CONDITION
• Visually inspect each valve stem and valve face for wear and
pitting.
• If it is worn or damaged, replace the valve with a new one.
CAUTION
CAUTION