VESPA LX 150 4T Euro 3 Service Station Manual page 17

Vespa LX 125 - 150 4T Euro 3
Slot packing system
- Provisionally fit the piston into the cylinder, without any base gasket.
- Assemble a dial gauge on the specific tool
- Set the dial gauge to zero at a contrast plane with an average preload, for example 5 mm. Keeping
the zero setting position, fit the tool on the cylinder and lock it with 2 nuts, as shown in the figure.
- Rotate the crankshaft up to the TDC (the inversion point of the dial gauge rotation)
- Calculate the difference between the two measurements: use the chart below to identify the thickness
of the cylinder base gasket to be used for refitting. Correctly identify the cylinder base gasket thickness
to keep the correct compression ratio.
- Remove the special tool and the cylinder.
Characteristic
Compression ratio (125/150)
10.6 ± 0.5 to 1
Specification
Value measured
Thickness
Value measured
Thickness
Value measured
Thickness
Specification
Value measured
Thickness
Value measured
Thickness
SHIMMING SYSTEM (125)
SHIMMING SYSTEM (150)
Characteristics
Desc./Quantity
0 - 0.1
0.8 ± 0.05
0.1 - 0.3
0.6 ± 0.05
0.3 - 0.4
0.4 ± 0.05
Desc./Quantity
1 - 1.1
0.8 ± 0.05
1.1 - 1.3
0.6 ± 0.05
CHAR - 17