KYMCO Super 8 50, Service Manual

Page: 84 / 185

7. CYLINDER HEAD/VALVES
7-1
Super 8 50
SERVICE INFORMATION
GENERAL INSTRUCTIONS

The cylinder head can be serviced with the engine installed in the frame.

When assembling, apply molybdenum disulfide grease or engine oil to the valve guide movable
parts, valve arm and camshaft sliding surfaces for initial lubrication.

The camshaft is lubricated by engine oil through the cylinder head engine oil passages. Clean and
unclog the oil passages before assembling the cylinder head.

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.
SPECIFICATIONS
Item Standard (mm) Service Limit (mm)
IN 0.04

EX 0.04

Cylinder head compression pressure 14kg/cm
²
Cylinder head warpage

0.05
IN 25.706 25.306
EX 25.564 25.164
IN 10.000
～
10.015 10.10
EX 10.000
～
10.015 10.10
Valve rocker arm shaft IN 9.972
～
9.987 9.91
O.D.
EX 9.972
～
9.987 9.91
IN 1.0 1.8
EX 1.0 1.8
IN 4.975
～
4.990 4.90
EX 4.955
～
4.970 4.90
IN 5.000
～
5.012 5.03
EX 5.000
～
5.012 5.03
Valve stem-to-guide IN 0.010
～
0.037 0.08
clearance
EX 0.030
～
0.057 0.10
SERVICE INFORMATION ...................... 7-1 CYLINDER HEAD DISASSEMBLY ....... 7-7
TROUBLESHOOTING............................. 7-2 CYLINDER HEAD ASSEMBLY ............. 7-8
CAMSHAFT REMOVAL ......................... 7-3 CYLINDER HEAD INSTALLATION ...... 7-8
CYLINDER HEAD REMOVAL .............. 7-5 CAMSHAFT INSTALLATION ................ 7-9
Valve clearance (cold)
Valve rocker arm I.D.
Valve stem O.D.
Valve guide I.D.
Valve seat width
Camshaft cam height