Valve Clearance - Honda CG125 Fan Owner's Manual

Owner´s Manual

Valve Clearance

(Refer to the Safety Precautions on page 39.)
Excessive valve clearance will cause noise and
eventual engine damage. Little or no clearance will
prevent the valve from closing and cause valve
damage and power loss. Check valve clearance when
the engine is cold at the specified intervals.
The checking or adjusting of the clearance should be
performed while the engine is cold. The clearance will
change as the engine temperature rises.
1. Remove the crankshaft hole cap and timing mark
hole cap.
2. Remove the cylinder head cover.
3. Rotate the generator flywheel counterclockwise until
the T mark (1) on the flywheel lines up with the
index mark (2) on the crankcase. In this position,
the piston may either be on the compression or
exhaust stroke.
(1) T mark
(2) Index mark
(2)
(1)
The adjustment must be made when the piston is at
the top of the compression stroke when both the
intake and exhaust valves are closed.
This condition can be determined by moving the
rocker arms. If they are free, it is an indication that
the valves are closed and that the piston is on the
compression stroke. If they are tight and the valves
are open, rotate the flywheel 360° and realign the
T mark to the index mark.
4. Check the clearance of both valves by inserting a
feeler gauge (3) between the adjusting screw (4) and
the valve stem.
Clearance should be:
Intake: 0.08 mm (0.003 in)
Exhaust: 0.08 mm (0.003 in)
If it is necessary to make an adjustment, loosen the
adjusting screw lock nut (5) and turn the adjusting
screw (4) so there is a slight resistance when the
feeler gauge (3) is inserted.
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