Precautions In Operation - Sym ATTILA RS-21 EFi 150 Service Manual

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 rocker arm.
• Cylinder head service cannot be carried out when engine is in frame.
Specification
Compression pressure
Camshaft Height of cam lobe
ID of valve rocker arm
Rocker
arm
OD of valve rocker arm shaft
OD of valve stem
Clearance between
Valve
valve stem and guide
Free length of valve spring
Connection Flatness of cylinder head
Torque Value
Cylinder head bolt
Cylinder head bolt (LH)
Cylinder head Nut
Sealing bolt of timing chain auto-tensioner
Bolt of timing chain auto-tensioner
Timing gear cover bolts
Spark plug
TOOLS
Special service tools
Valve reamer: 5.0mm
Valve guide driver: 5.0mm
Valve spring compressor
6-2
This chapter Contents
Item
Intake
Exhaust
Intake
Exhaust
Guide seat
Intake
Exhaust
Valve seat width
Standard
12 ± 2 kg/cm²
25.688
25.519
12.000~12.015
11.966~11.984
4.975~4.990
4.950~4.975
5.000~5.012
0.010~0.037
0.025~0.062
35.000
1.000
-
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
Unit: mm
Limit
-
25.290
25.120
12.100
11.910
4.900
4.900
5.030
0.080
0.100
31.500
1.600
0.050