Sym Fiddle III 50 Service Manual

6. CYLINDER HEAD/VALVE SYM
6-2
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 unit: mm
Item Standard Limit
Compression pressure
12.2±0.2:1
kg/cm²
-
Intake 25.686~25.786 25.29
Camshaft Height of cam lobe
Exhaust 25.50~25.60 25.12
ID of valve rocker arm 10.000~10.015 10.10
Rocker
arm
OD of valve rocker arm shaft 9.972~9.987 9.910
Intake 4.975~4.99 4.90
OD of valve stem
Exhaust 4.955~4.97 4.90
ID of Guide 5.000~5.015 5.030
Intake 0.010~0.037 0.080
Clearance between
valve stem and guide
Exhaust 0.030~0.057 0.100
Outer 35.25
-
Valve
Free length of valve
spring
Inner 32.26~32.56
-
Torque Value
Cylinder head cover bolt 0.8~1.2kgf-m
Cylinder head bolt (LH) 0.8~1.2kgf-m
Bolt of timing chain auto-adjuster 0.8~1.2kgf-m
Spark plug 1.0~1.4kgf-m
Cylinder head nut 0.8~1.2kgf-m
Valve adjustment fixing nuts 0.7~1.1kgf-m
TOOLS
Special service tools
Valve reamer: 5.0mm
Valve guide driver: 5.0mm
Valve spring compressor

Sym Fiddle III 50 Specifications

General

Brand	Sym
Model	Fiddle III 50
Category	Scooter
Language	English