APRILIA STX 150 User Manual

Maximum clearance between the piston and
cylinder
0.025 / 0.035 mm (0.00098 / 0.00138 in)
PISTON RINGS
•
Clean off any carbon deposits from the grooves in the piston rings and from the rings them-
selves.
•
Measure the piston ring side clearance and replace the piston and the piston rings all to-
gether if not complying with specifications.
Piston ring side clearance:
Characteristic
Top ring
0.15 / 0.35 mm (0.0059 / 0.0138 in)
Middle ring
0.15 / 0.35 mm (0.0059 / 0.0138 in)
Oil scraper ring
0.15 / 0.60 mm (0.0059 / 0.0236 in)
•
Fit the piston ring to the cylinder.
•
Level the installed piston ring with the
piston crown.
•
Measure piston ring port and replace it
if not complying with specifications.
CAUTION
IT IS NOT POSSIBLE TO MEASURE THE OIL SCRAPER
RING END LIGHT: IF THERE IS AN EXCESSIVE CLEAR-
ANCE, REPLACE THE THREE PISTON RINGS.
PIN
•
Clean off combustion residues from the piston crown and from the area above the top ring.
•
Check for cracks on the piston and for compression on the piston sliding surface (seizing);
Replace the piston if required.
•
Measure the pin outside diameter (1)
and if not complying with specifica-
tions, replace the pin.
Characteristic
Pin outside diameter
14.998 / 14.992 mm (0.5905 / 0.5902 in)
Engine ETX - STX 150
ENG - 106

APRILIA STX 150 Specifications

General

Brand	APRILIA
Model	STX 150
Category	Motorcycle
Language	English