Service Information - KYMCO VENOX 250 Service Manual

6
. CYLINDER HEAD/VALVES

SERVICE INFORMATION

GENERAL INSTRUCTIONS
• When assembling, apply engine oil to the valve guide movable parts, valve arm and camshaft
sliding surfaces for initial lubrication.
• The valve rocker arm is lubricated with engine oil through the cylinder head engine oil passages.
Clean and unclog the oil passages before cylinder head assembly.
• After disassembly, clean the removed parts and dry them with compressed air before inspection.
• After removal, mark and arrange the removed parts in order. When assembling, install them in
the reverse order of removal.
• The cylinder head and holder need to be replaced if anyone broken.
SPECIFICATIONS
Item
Valve clearance (cold)
Compression pressure (kg/cm²)
Cylinder head warpage
Camshaft cam height
Camshaft height
Rocker arm I.D.
Rocker arm shaft O.D.
Rocker arm-to-shaft
clearance
Valve seat angle
Valve stem O.D.
Valve guide I.D.
Valve spring free
length
Valve stem-to-guide
clearance
Standard (mm)
VENOX250
IN 0.1mm
EX 0.1mm
IN
EX
R 23.978~23.990
C 23.90~23.920
L 23.978~23.990
IN 10.0~10.015
EX 10.0~10.015
IN 9.975~9.990
EX 9.975~9.990
IN
EX
IN 90º+1.0
EX 90º+1.0
IN 4.975~4.990
EX 4.975~4.990
IN 4.95~5.0
EX 4.95~5.0
IN Inner:29.8 Outer:33.6
EX Inner:29.8 Outer:33.6
IN
EX
17±2
—
34.40
34.40
0.04
0.04
0.175
0.155
VENOX 250
Service Limit (mm)
VENOX250
—
—
—
0.1
—
—
23.90
23.80
23.90
10.040
10.040
9.94
9.94
—
—
—
—
4.90
4.90
5.05
5.05
Inner:29.8 Outer:33.6
Inner:29.8 Outer:33.6
—
—
6-2