PIAGGIO Liberty 125, Workshop Manual, Page: 95 / 212

Inspecting the piston rings
- Alternately insert the three sealing rings into the cylinder, in the area where it retains its original di-
ameter. Using the piston, insert the rings perpendicularly to the cylinder axis.
- Measure the opening, see figure, of the sealing rings using a thickness gauge.
- If any measurements are greater than specified, replace the piston rings.
N.B.
BEFORE REPLACING ONLY THE PISTON RINGS, ENSURE THAT THE CLEARANCE BETWEEN
THE PISTON RINGS AND THE PISTON RING GROOVES, AND BETWEEN THE PISTON AND THE
CYLINDER, IS AS SPECIFIED. IN ANY CASE, NEW PISTON RINGS USED IN COMBINATION WITH
A USED CYLINDER MAY HAVE DIFFERENT BEDDING CONDITIONS THAN THE STANDARD.
SEALING RINGS (125)
Name Description Dimensions Initials Quantity
Compression ring 57 x 1 A 0.15 ÷ 0.30
Oil scraper ring 57x1 A 0.10 ÷ 0.30
Oil scraper ring 57x2.5 A 0.10 ÷ 0.35
Compression ring 1st
oversize
57.2 x 1 A 0.15 ÷ 0.30
Oil scraper ring 1st
oversize
57.2x1 A 0.10 ÷ 0.30
Oil scraper ring 1st
oversize
57.2x2.5 A 0.10 ÷ 0.35
Compression ring 2nd
oversize
57.4x1 A 0.15 ÷ 0.30
Oil scraper ring 2nd
oversize
57.4x1 A 0.10 ÷ 0.30
Oil scraper ring 2nd
oversize
57.4x2.5 A 0.10 ÷ 0.35
Compression ring 3rd
oversize
57.6x1 A 0.15 ÷ 0.30
Oil scraper ring 3rd
oversize
57.6x1 A 0.10 ÷ 0.30
Oil scraper ring 3rd
oversize
57.6x2.5 A 0.10 ÷ 0.35
Maximum clearance after use: 1 mm
MAX. VALUE (125)
Name Description Dimensions Initials Quantity
Top piston ring 0,40
Middle piston ring 0,40
Oil scraper 0,45
SEALING RINGS (200)
Name Description Dimensions Initials Quantity
Compression ring 72x1.5 A 0.15 ÷ 0.30
Oil scraper ring 72x1 A 0.20 ÷ 0.40
Oil scraper ring 72x2.5 A 0.20 ÷ 0.40
MAX. VALUE (200)
Name Description Dimensions Initials Quantity
Top piston ring 0,40
Middle piston ring 0,50
oil scraper 0,50
Liberty 125 - 200 4tempi
Engine
ENG - 95