PIAGGIO Beverly Tourer 125, Service Station Manual

Page: 18 / 278

Measurement « A » to be taken, is a value of piston protrusion. It indicates by how much the plane formed
by the piston crown protrudes from the plane formed by the upper part of the cylinder. The further the
piston protrudes from the cylinder, the thicker the base gasket to be used (to restore the compression
ratio) and vice versa.
N.B.
NO GASKETS AND SEALS SHOULD BE ASSEMBLED BETWEEN THE CRANKCASE AND CYL-
INDER AND THE DIAL GAUGE EQUIPPED WITH SUPPORT SHOULD BE SET TO ZERO FOR
MEASUREMENT «A» TO BE TAKEN WITH THE PISTON AT TOP DEAD CENTRE POSITION AND
ON A RECTIFIED PLANE.
M
ODELS WITH METAL HEAD GASKET
(0.3)
Name Measure A Thickness
Shimming - Cylinder 67.8 - Head gasket
0.3 - Base gasket 0.4
1.40 ÷ 1.65 0.4 ± 0.05
Shimming - Cylinder 67.8 - Head gasket
0.3 - Base gasket 0.6
1.65 ÷ 1.90 0.6 ± 0.05
Characteristic
Compression ratio
12 ± 0.5: 1
Characteristics
Beverly 125
CHAR - 18