PIAGGIO MSS ZIP 100 4T, Service Manual

Page: 94 / 192

Specification Desc./Quantity
Measure detected 1 ± 0.05
Base gasket thickness 0.5
CYLINDER BASE GASKET THICKNESS
Specification Desc./Quantity
Cylinder height 57.15 ± 0.05
Head gasket thickness (steel) 0.3 ± 0.05
Measure detected 0.20 ± 0.05
Base gasket thickness 0.4
Measure detected 0.30 ± 0.05
Base gasket thickness 0.5
This engine is manufactured with two different head gasket solutions:
- Fibre gasket drw. 969244 0.95 mm thick.
- Steel gasket drw. 969393 0.3 mm thick.
In order to guarantee an adequate compression ratio, the gaskets match cylinders with different heights:
- Fibre gaskets with cylinder 56.45 mm high
- Fibre gaskets with cylinder 57.15 mm high
In order to carry out the revision both gaskets should be present on the spare parts.
All pin-piston-cylinder units supplied with the spare parts present cylinders 57.15 mm high
N.B.
MEASUREMENT "A" TO BE TAKEN IS A VALUE OF PISTON RE-ENTRY, IT INDICATES BY HOW
MUCH THE PLANE FORMED BY THE PISTON CROWN FALLS BELOW THE PLANE FORMED BY
THE TOP OF THE CYLINDER. THE FURTHER THE PISTON GETS INSIDE THE CYLINDER, THE
THINNER THE HEAD GASKET TO BE APPLIED SHOULD BE (TO RECOVER THE COMPRESSION
RATIO) AND VICE VERSA.
Characteristic
Shimming system to control the compression ratio
CR: 11.1 ÷ 12.9
PISTON PROTRUSION CHECK
Name Measure A Thickness
shimming_1 0.05 ÷ 0.25 0.35
shimming_2 0.25 ÷ 0.40 0.25
Engine
MSS ZIP 100 4T
ENG - 94