Inspecting The Small End; Inspecting The Wrist Pin - PIAGGIO Fly 150 4T Workshop Manual

Fly 125 - 150 4T
- Remove the two stop rings, the wrist pin and the
piston.
- Remove the 3 piston rings from the piston.
N.B.
BE CAREFUL NOT TO DAMAGE THE PISTON
RINGS DURING REMOVAL.

Inspecting the small end

- Measure the internal diameter of the small end
using an internal micrometer.
N.B.
IF THE DIAMETER OF THE ROD SMALL END
EXCEEDS THE MAXIMUM DIAMETER AL-
LOWED, SHOWS SIGNS OF WEAR OR OVER-
HEATING REPLACE THE CRANKSHAFT AS
DESCRIBED IN THE "CRANKCASE AND
CRANKSHAFT" CHAPTER".
Characteristic
Rod small end check-up: Maximum diameter
15.030 mm
Rod small end check-up: Standard diameter
15 +0.015+0.025 mm

Inspecting the wrist pin

- Check the outer diameter of the gudgeon pin.
Characteristic
Standard pin diameter
14.996 ÷ 15 mm
Minimum diameter permitted
Ø 14.994 mm
Engine
ENG - 109