PIAGGIO Beverly 300 i.e. - Page 14

- Measure the diameter of the bearings on the pis-
ton.
Characteristic
Standard diameter
16 +0.006 +0.001 mm
- Calculate the piston pin coupling clearance.
N.B.
THE PIN HOUSINGS HAVE 2 LUBRICATION CHANNELS. FOR THIS REASON, MEASUREMENT
MUST BE MADE ACCORDING TO THE PISTON AXIS
Characteristic
Standard clearance:
0.001 - 0.010 mm
- Carefully clean the seal housings.
- Measure the coupling clearance between the
sealing rings and the piston grooves using suitable
sensors, as shown in the diagram.
- If the clearance is greater than that indicated in
the table, replace the piston.
N.B.
MEASURE THE CLEARANCE BY INSERTING THE BLADE
OF THE FEELER GAUGE FROM THE SECOND SEAL RING
SIDE.
Fitting clearance
Top piston ring - standard coupling clearance
0.015 - 0.06 mm Top piston ring - maximum clear-
ance allowed after use 0.07 mm Middle piston
ring - standard coupling clearance 0.015 - 0.06 mm
Middle piston ring - maximum clearance al-
lowed after use 0.07 mm oil scraper ring - stand-
ard coupling clearance 0.015 - 0.06 mm oil scraper
ring - maximum clearance allowed after use
0.07 mm
Characteristics Beverly 300 i.e.
CHAR - 14