VESPA ET4 50, Workshop Manual

Page: 65 / 185

020456Y Ø 24 mm adaptor
020362Y 12 mm guide
020171Y Punch for Ø 17 mm roller case
Inspecting the clutch spring
- Check that the contrast spring of the driven pulley
does not show signs of deformation
- Measure the free length of the spring
Characteristic
Standard length
118 mm
Minimum length allowed after use
XXXX
- Check the thickness of the clutch mass friction
material.
-The masses must not show traces of lubricants;
otherwise, check the driven pulley unit.
N.B.
UPON RUNNING-IN, THE MASSES MUST EXHIBIT A CEN-
TRAL CONTACT SURFACE AND MUST NOT BE DIFFER-
ENT FROM ONE ANOTHER. VARIOUS CONDITIONS CAN
CAUSE THE CLUTCH TO TEAR.
CAUTION
DO NOT OPEN THE MASSES USING TOOLS SO AS TO
PREVENT A VARIATION IN THE RETURN SPRING LOAD.
Characteristic
Minimum thickness permitted:
1 mm
Refitting the clutch
- Preassemble the driven pulley group with spring,
sheath and clutch.
- Position the spring with the sheath
- Insert the components in the tool and preload the
spring being careful not to damage the plastic
sheath and the end of the threaded bar.
ET4 50
Engine
ENG - 65