Checking The Valve Guides - MOTO GUZZI Norge 1200 Service Manual

Norge 1200
•
Remove the upper retainer (2).
•
Remove the internal spring (3).
•
Remove the external spring (4).
•
Remove the lower retainer (5) and the
shimming washers if necessary.
•
Remove the valve (6) from inside the
head.

Checking the valve guides

Use a punch to extract the valve guides from the
heads.
The valve guides should be replaced only if the
clearance between them and the stem cannot be
eliminated by simply replacing the valves.
To refit the valve guides on the head, follow this
procedure:
•
Heat the head in an oven at about 60°
C (140°F).
•
Lubricate the valve guide.
•
Fit the circlips.
•
Press the valve guide with a punch.
•
Use a reamer to bore the holes the
valve stems slide through so that the
inside diameter is at the prescribed val-
ue. The interference between the seat
on the head and the valve guide must
be 0.046 - 0.075 mm (0.0018 - 0.0030
in)
VALVE AND GUIDES COUPLING DATA
CHART (INLET)
Specification
Valve guide inside di-
ameter mm (in)
Valve stem diameter
Fitting clearance mm
(in)
Desc./Quantity
8.000 ÷ 8.022 (0.3150 ÷
0.3158)
7.972 ÷ 7.987 (0.3139 ÷
0.3145)
0.013 ÷ 0.050 (0.0005 ÷
0.0020)
Engine
ENG - 39