Sym Symply50 User Manual

SYM 6. CYLINDER HEAD/VALVE
6-9
Caution
Correct it with reamer after replacement.
If clearance still exceeds service limit after
replaced valve guide, replace valve stem too.
Caution
Valve guide replacement
Heat up cylinder head to 100~150 ℃ with
heated plate or toaster.
Caution
Hold the cylinder head, and then press out old
valve guide from combustion chamber side.
Tool: Valve guide driver 5 mm
Caution
Adjust the valve guide driver and let valve
guide height is in 13mm.
Press in new valve guide from rocker arm side.
Tool: Valve guide driver 5 mm
Wait for the cylinder head cooling down to
room temperature, and then correct the new
valve guide with reamer.
Caution
Correct valve seat, and clean up all metal
residues from cylinder head.
Special tool: Valve guide reamer 5 mm
If clearance between valve stem and valve
guide exceeded service limit, check whether
the new clearance that only replaces new
valve guide is within service limit or not. If
so, replace valve guide.
It must correct valve seat when replacing
valve guide.
 Do not let torch heat cylinder head directly.
Otherwise, the cylinder head may be
deformed as heating it.
 Wear on a pair of glove to protect your
hands when operating.

Check if new valve guide is deformation
after pressed it in.
 When pressing in the new valve guide,
cylinder head still must be kept in 100~150
℃.

Using cutting oil when correcting valve
guide with a reamer.
 Turn the reamer in same direction when it
be inserted or rotated.
V
alve guide drive
r
5.0mm
V
alve guide drive
r
5.0mm
13 mm
(0.15in)
Valve guide reamer 5.0mm

Sym Symply50 Specifications

General

Brand	Sym
Model	Symply50
Category	Scooter
Language	English