Sym Orbit 125 Service Manual page 64

6. CYLINDER HEAD/VALVE
PRECAUTIONS IN OPERATION
General Information
This chapter is contained maintenance and service for cylinder head, valve, and camshaft
as well as valve rocker arm.
Cylinder head service cannot be carried out when engine is in frame.
Specification
Compression pressure
Height of cam lobe
Camshaft
Rocker
arm
OD of valve rocker arm shaft
OD of valve stem
Clearance between
valve stem and guide
Valve
Free length of valve
Connection Flatness of cylinder head
Torque Value
Cylinder head cover bolt
Cylinder head bolt (LH)
Cylinder head Nut
Sealing bolt of timing chain auto-adjuster
Bolt of timing chain auto-adjuster
Timing gear cover bolts
Spark plug
TOOLS
Special service tools
Valve reamer: 5.0mm
Valve guide driver: 5.0mm
Valve spring compressor
6-2
Item
ID of valve rocker arm
OD of Guide
spring
Valve seat width
12 ± 2 kg/cm²
Intake
Exhaust
Intake
Exhaust
Intake 0.010~0.037
Exhaust 0.030~0.057
Outer
Inner
1.0~1.4kgf-m
1.0~1.4kgf-m
1.8~2.2kgf-m (apply with oil on bolt thread & seat)
0.8~1.2kgf-m
1.0~1.4kgf-m
0.7~1.1kgf-m (apply with oil on bolt thread & seat)
1.0~1.4kgf-m
Standard
25.736
25.55
10.00 10.000~10.015
10.00 9.985~10.00
5.00 4.975~4.99
5.00
5.00
32.56
35.25 34.75~35.75
1.000
-
SYM
unit: mm
Limit
-
-
-
4.97~4.98
5.030
0.080
0.100
32.26
1.600
-