PIAGGIO 2005 XEVO 400ie, Руководство по ремонту

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This selection is useful to keep the difference between the working distance of the gears and their
distance without clearance at a given value in order to avoid abnormal noise.
TYPE A
Specification Desc./Quantity
Centre to centre distance of the gears without clearance 76.937 ÷ 76.867
Centre to centre distance on the crankcase 77.022 ÷ 76.992
TYPE B
Specification Desc./Quantity
Centre to centre distance of the gears without clearance 76.907 ÷ 76.837
Centre to centre distance on the crankcase 76.992 ÷ 76.962
The gears with centre to centre distance without clearance between 76.867 and 76.907 are considered
universal and can be fitted to either crankcase type.
Either the pair of gears or the crankcase is identified with the letter referring to the type (on the crank-
case, this mark is found at the cylinder mouth, flywheel side).
Slot packing system
Shimming system for keeping the compression ra-
tio
DISTANCE «A» IS A PROTRUSION OR RECESS VALUE OF
THE PISTON CROWN WITH RESPECT TO THE CYLINDER
PLANE.
DISTANCE «A» HELPS DETERMINE THE THICKNESS OF
GASKET «B» THAT HAS TO BE FITTED TO THE CYLINDER
HEAD IN ORDER TO RESTORE COMPRESSION RATIO.
BASE GASKET «B» MUST BE THICKER THE MORE THE
PLANE FORMED BY THE PISTON TOP PROTRUDES
FROM THE PLANE FORMED BY THE CYLINDER HEAD. ON
THE OTHER HAND, THE MORE THE PISTON TOP IS RE-
CESSED INTO THE CYLINDER TOP PLANE, THE SMALL-
ER THE GASKET THICKNESS.
Characteristic
Compression ratio
10.6 ± 0.5 : 1
BASE GASKET THICKNESS
Name Measure A Thickness
«A» MEASURE TAKEN - 0.185 - - 0.10 0.4 ± 0.05
«A» MEASURE TAKEN - 0.10 - + 0.10 0.6 ± 0.05
«A» MEASURE TAKEN + 0.10 ÷ + 0.185 0.8 ± 0.05
N.B.
VALUES INDICATED WITH «-» REFER TO PISTON CROWN RECESSES WITH RESPECT TO THE
CYLINDER PLANE.
N.B.
DISTANCE «A» MUST BE MEASURED WITHOUT ANY GASKET FITTED AT «B»
Characteristics
XEVO 400ie
CHAR - 14