Suzuki GN125F, Service Manual

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E N G I N E
3-10
VALVE SPRING
09900 20103: Vernier calipers -
Measure the valve spring free length.
Measure the thickness , and if the thickness is found to
have been reduced to the limit, replace the valve.
Check the spark plug hole and valve of combustion chamber
part for scratch.
Check the gasketed surface of the cylinder head for distor-
tion with a straightedge and thickness gauge.
Check the valve stem for bending, pitting or abnormal wear.
Measure the valve stem O.D.
CYLINDER HEAD
09900-20803:Thickness gauge
VALVE STEM
09900-20205 : Micrometer (0~25 mm)
Visually inspect each valve for wear of its seating
face. Replace any valve with an abnormally worn face.
Valve stem O.D.:
IN.: 4.975-4.99 mm EX.: 4.955-4.97 mm
Valve spring free length imit:
IN.: 31.24 mm EX.: 33.58 mm
Cylinder head distortion limit: 0.05 mm
Valve face thickness limit: 0.5 mm
09900-20606: Dial gauge (1/100 mm)
09900-20701: Magnetic stand
09900-21304: V-block ( 100 mm)
Measure the runout with a dial gauge Replace the cam-
shaft if the runout exceeds the limit.
.
Camshaft runout limit: 0.1 mm
A
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