Checking Piston Rings; Checking Piston Gudgeon Pin - APRILIA QUASAR 125 2003 Workshop Manual

ENGINE
QUASAR 125-180

3.2.26 CHECKING PISTON RINGS

Measure piston rings side clearance with a feeler gauge.
Side clearance: 0.12 mm
Check piston rings carefully. Distance between the two ends shall be 0.5 mm.
To check, use a feeler gauge and insert the piston ring horizontally inside the
cylinder. To do so, position the piston ring squarely with the cylinder using the
bare piston.
Position piston ring inside its original location on cylinder upper side.

3.2.27 CHECKING PISTON GUDGEON PIN

Carefully inspect gudgeon pin: it must be perfectly smooth, without scorings,
steps or blueish stains due to overheating. In case of scores or steps, or if
blueish/greyish stains are present, change the gudgeon pin. In case the
gudgeon pin colour is slightly matt, do not change it.
Measure gudgeon pin outer diameter (D).
Gudgeon pin outer diameter:
14.960 mm.
Check gudgeon pin seat diameter.
Gudgeon pin seat diameter:
15.04 mm.
Check gudgeon pin seat diameter inside the connecting rod.
Connecting rod inner diameter:
15.06 mm.
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Release 00/2003 - 09