Cylinder Gasket Selection - PIAGGIO 500 cc Service Manual

- Assemble the gudgeon pin lock using the pin, as
shown in the figure.
Specific tool:
Tool for gudgeon pin lock assembly
N.B.: The stop rings assembly tool must be used by
hand.
Warning
- Using a hammer may damage the locks
housing.

Cylinder gasket selection

- Temporarily assemble the cylinder on the piston
without its gasket.
- Fit a dial gauge on the specific tool using the short
connection, as shown in the figure.
Specific tool:
Stand for piston position check
- Set the dial gauge to zero with a preload of a few
millimeters by means of a surface plate,
- Fix the dial gauge.
- Check that the feeler pin is sliding perfectly.
- Assemble the tool on the cylinder without changing
the dial gauge position.
- Lock the tool using the head fixing original nuts.
- Move the driving shaft up to the TDC (dial gauge
reversal of rotation point).
- Measure the deviation from the zero setting value.
- Consult the table below to find the thickness of the
cylinder gasket to be used for reassembly. Identifying
the right cylinder gasket thickness will allow to main-
tain the right compression ratio.
- Remove the specific tool and the cylinder.
N.B.: If the deviation (projection or recess) is near to the
change of class, repeat the measurement on the oppo-
site side. Reassemble the tool by inverting its position.
Measured recess / projection
- 0.185 - - 0.10
- 0.10 - + 0.10
+ 0.10 - + 0.185
020470Y
020475Y
Thermal unit and timing system
Gasket thickness
0.4 ± 0.05
0.6 ± 0.05
0.8 ± 0.05
05_192
05_193
7
05_194
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