Valve/Tappet Gap
Adjustment
After approximately one hour of
operation, tappet gap adjustment may
be necessary. When you check the
valves, lubricate the moveable parts.
Also make sure the screw is in tight
before making adjustments to valves.
Adjust the valves to a clearance of
.03mm to .10mm (.002" – .004") using
the supplied gauge. The valves must
be adjusted with the engine cold due to
thermal expansion.
Note: Valves must be in the
compression stroke or closed position
as shown in Figure 2 below. When
adjustment is completed, make sure
you tighten the lock nut.
Carburetor
Maintenance
Should you experience difficulty with
the carburetor of your engine:
1.
Remove the high-speed needle (85)
and flush out the spray bar with clean
fuel. Replace the high-speed needle
and follow the instructions in the
Carburetor Adjustment section.
2.
Factory settings for the idle needle
valve for engines 120 thru 220a are
shown in the figure below.
E N G I N E O P E R A T I O N
9
Engine Maintenance
Do not needlessly dismantle your
Saito
™
single cylinder engine.
If you must disassemble your single
cylinder engine, please refer to the
following steps. Remember, a qualified
individual should do disassembly.
1.
Cylinder screws should be loosened
in a criss-cross pattern.
2.
Assemble the cam gear lining up
the timing mark at the “6 o’clock”
position. The crankshaft must be
positioned at the “12 o’clock”
or “top dead center” (TDC) position
(refer to Figure 1 below).
3.
Reassemble the piston, rod, rocker
arm, pins, pushrod, tappet, etc. in their
original positions. Engine parts are
mated after running the engine and
they must be reassembled as close as
possible to their original position.
4.
Assemble the engine, reversing
the criss-cross pattern used in the
disassembly. Prior to tightening each
of the screws, apply a drop of oil to
prevent thread damage.
Normal engine maintenance, such
as adjusting the valves or carburetor
maintenance, is permissible without
voiding the warranty.
If you have
any questions concerning
maintenance procedures, please
contact the Saito Service Center
at (217) 355-9511.
Our technicians
will be happy to advise you on
maintenance issues.
8
N O R M A L E N G I N E O P E R A T I O N
Cam (Intake or Exhaust)
Bench Mark
Figure 1
Tappet Adjustment
Adjust between
0.03 – 0.10mm (.002" – .004")
Gauge
(0.1mm Max.)
Screw
Figure 2
High speed needle valve
Fuel nipple
Cap screw(M3X8)
Throttle lever
(-)Screw driver
Clockwise direction
For lean mixture
Idle needle valve
Counter-clokwise direction
For rich mixture
Standard Values
Throttle lever
Throttle valve
Idle needle value
Out of about 0.5mm
Into about 0.8 mm
Into about
1
½
turns
(Flush to the lever)
120S , 150S
Standard face
Out of about 1 turns
180 , 220a
