VESPA LX 4T USA, Workshop Manual

Page: 97 / 194

Inspecting the cam shaft
- Inspect the cam shaft for signs of abnormal wear
on the cams.
Characteristic
Standard diameter - Bearing A:
Ø 12 +0.002 +0.010
mm
Standard diameter - Bearing B:
Ø 16-0.015 -0.023 mm
Minimum diameter allowed - Bearing A:
Ø 11.98 mm
Minimum diameter allowed - Bearing B:
Ø 15.96 mm
- If any of the above dimensions are outside the
specified limits, or there are signs of excessive
wear, replace the defective components with new
ones.
N.B.
A BALL BEARING IS FITTED ON BEARING «A»; CONSE-
QUENTLY, BEARING «B» IS THE MOST IMPORTANT AS IT
WORKS DIRECTLY ON THE HEAD ALUMINIUM
Characteristic
Standard height - Intake:
25.935 mm
Standard height - Discharge:
25.935 mm
Fitting clearance
Maximum admissible axial clearance
0.5 mm
- Check there are no signs of scoring or wear on
the rocking lever bolt.
- Measure the diameter « A ».
- Measure the internal diameter of each rocking
lever. level « B ».
Check there are no signs of wear on the pad from
contact with the cam and on the jointed adjustment
plate.
- In case of anomalies, replace the damaged com-
ponents.
Characteristic
LX 4T USA
Engine
ENG - 97