APRILIA SCARABEO 500 - 2008, Service Station Manual

Page: 28 / 324

Characteristic
Crankshaft-crankcase axial clearance:
0.1 ÷ 0.405 mm
Slot packing system
Shimming system to control the compression ratio
MEASUREMENT «A» IS A PROTRUSION OR
RECESS VALUE OF THE PISTON CROWN
COMPARED WITH THE CYLINDER PLANE.
MEASUREMENT «A» ALLOWS TO DETER-
MINE THE THICKNESS OF GASKET «B» THAT
HAS TO BE FITTED INTO THE CYLINDER
BASE IN ORDER TO RESTORE THE COM-
PRESSION RATIO. THE MORE THE PLANE
FORMED BY THE PISTON CROWN PRO-
TRUDES BEYOND THE PLANE FORMED BY
THE CYLINDER UPPER END, THE THICKER
THE GASKET TO BE USED AT THE CYLINDER
BASE «B» SHOULD BE. ON THE OTHER
HAND, THE MORE THE PISTON CROWN IS RE-
CESSED INTO THE CYLINDER TOP PLANE,
THE SMALLER THE GASKET THICKNESS.
Characteristic
Compression ratio
10.5: 1
BASE GASKET THICKNESS
Name Measure A Thickness
MEASURE TAKEN «A» - 0.185 ÷ - 0.10 0.4 ± 0.05
MEASURE TAKEN «A» - 0.10 ÷ + 0.10 0.6 ± 0.05
MEASURE TAKEN «A» + 0.10 ÷ + 0.185 0.8 ± 0.05
NOTE
VALUES INDICATED WITH «-» REFER TO RECESSES OF THE PISTON CROWN FROM THE
CYLINDER PLANE.
NOTE
SIZE «A» MUST BE MEASURED WITHOUT ANY GASKET FITTED AT «B»
Characteristics
SCARABEO 500
CHAR - 28