Sym PA12B User Manual

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7. Cylinder Head / Valve
Precautions in Operation
General Information
This chapter includes the repair information of cylinder head, valve, camshaft, and rocker arm.
The engine must be removed before the repairing of Cylinder head.
Specification Measurement unit :mm
Specification
Subject
Standard Service Limit
Valve Clearance (IN/EX valve when
engine is cold)
0.05 ± 0.02 ─
Compression pressure 12 ± 1 kg/cm² ─
IN 31.983 30.800
Camshaft
Cam Lift
EX 31.119 30.020
Inner Diameter 12.000~12.018 12.100
Rocker
Arm
Outer Diameter 11.984~11.966 12.000
IN 5.450~5.465 5.420
Valve
stem outer
diameter
EX 5.430~5.455 5.400
IN 5.4750~5.485 5.500
Valve
guide
EX 5.4750~5.485 5.500
IN 0.010~0.035 0.080
Clearance
between
Valve stem
and
g
uide
EX 0.030~0.055 0.100
Valve
Guide
Valve seat width 1.200 1.600
Warpage/clearance between cylinder head
and cylinder.
─ 0.050
Torque Value
Cylinder head nuts 2.8~3.0kgf-m Cylinder head tensioner bolt 1.0~1.4kgf-m
Cylinder head left bolts 0.8~1.2kgf-m Tappet adjusting cap 1.3~1.7kgf-m
Cylinder head side cover bolts 0.8~1.2kgf-m Valve adjusting holding nut 0.7~1.1kgf-m
(Apply engine oil on threads and seats.) Cam chain sprocket bolt 0.8~1.2kgf-m
Rocker arm shaft setting plate bolts
0.8~1.2kgf-m
Spark plug 1.0~1.2kgf-m
Special tools
Valve Guide reamer 5.0mm
Valve Guide driver 5.0mm
7-2
Rocker arm shaft/ Camshaft Disassemble tool
SYM-1445100
Valve Spring Compressor SYM-1471100
Valve Spring Assemble/Disassemble Tool
SYM-1471110/20
Cylinder Head/ Engine Oil Strainer Cap
Wrench SYM-ALL23461
Valve Clearance Adjustment Wrench
SYM-9001200

Sym PA12B Specifications

General

Brand	Sym
Model	PA12B
Category	Motorcycle
Language	English