VESPA 633844 IT Service Manual page 99

Vespa GTV 250 i.e.
Inspecting the clutch drum
- Check that the clutch bell is not worn or damaged.
- Measure the clutch bell inside diameter.
Characteristic
Max. value clutch bell
Max. value: Ø 134.5 mm
Clutch bell standard value
Standard value: Ø 134 - 134.2 mm
Checking the bell working surface eccentricity
- Install the bell on a driven pulley shaft using 2
bearings (inner diameter 15 and 17 mm).
- Lock with the original spacer and nut.
- Place the bell/shaft assembly on the support to
check the crankshaft alignment.
- Using a feeler pin gauge and the magnetic base,
measure the bell eccentricity.
- Repeat the measurement in 3 positions (Central,
internal, external).
- If faults are found, replace the bell.
Specific tooling
020074Y Support base for checking crankshaft
alignment
020335Y Magnetic support for dial gauge
Characteristic
clutch bell inspection: Limit eccentricity.
Admissible limit eccentricity: 0.15 mm
Engine
ENG - 5