Installing The Cylinder Head - APRILIA MSS Mana GT ABS Service Station Manual

MSS Mana GT ABS
- By means of the chart, identify the thickness of the cylinder base gasket to be used upon refitting. By
correctly identifying the cylinder base gasket thickness, an adequate compression ratio can be main-
tained
- Remove the specific tool and the cylinder.
NOTE
IF DEVIATIONS (PROTRUSIONS OR RECESSES) CLOSE TO THE CHANGE OF CATEGORY ARE
MEASURED, REPEAT THE MEASUREMENT AT THE OPPOSITE SIDE. TO DO SO, REPEAT THE
TOOL FITTING OPERATION, INVERTING ITS POSITION.
MEASUREMENT «A» IS A PROTRUSION OR RECESS VAL-
UE OF THE PISTON CROWN COMPARED WITH THE CYL-
INDER PLANE.
MEASUREMENT «A» ALLOWS TO DETERMINE THE
THICKNESS OF THE GASKET «B» THAT HAS TO BE FIT-
TED INTO THE CYLINDER BASE IN ORDER TO RESTORE
THE COMPRESSION RATIO. THE MORE THE PLANE
FORMED BY THE PISTON CROWN PROTRUDES BEYOND
THE PLANE FORMED BY THE CYLINDER UPPER END,
THE THICKER THE GASKET TO BE USED AT THE CYLIN-
DER BASE «B» SHOULD BE. ON THE OTHER HAND, THE
MORE THE PISTON CROWN IS RECESSED INTO THE CYL-
INDER TOP PLANE, THE SMALLER THE GASKET THICK-
NESS.
Characteristic
Compression ratio
10.5 ± 0.5 : 1
Name
MEASURE TAKEN «A»
MEASURE TAKEN «A»
MEASURE TAKEN «A»
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»

Installing the cylinder head

- The head is fitted in two separate stages.
- According to the indications described, fit the rear cylinder head and then the front cylinder head.
BASE GASKET THICKNESS
Measure A
- 0.185 ÷ - 0.10
- 0.10 ÷ + 0.10
+ 0.10 ÷ + 0.185
Engine
Thickness
0.4 ± 0.05
0.6 ± 0.05
0.8 ± 0.05
ENG - 203