Gilera 633721, Workshop Manual

Page: 146 / 407

Characteristic
Maximum allowable run-out:
0.1 mm
- In case of irregularities, replace the head.
- Check the sealing surfaces for the intake and ex-
haust manifold.
- Check that the bearings of the camshaft and the
rocker pins exhibit no wear.
- Check that the head cover surface is not worn.
- Check that the coolant sealing pad exhibits no
oxidation.
STANDARD DIAMETER
Specification Desc./Quantity
A 13 + 0.018 0
B 20 + 0.021 0
C 42 + 0.025 0
- If wear is discovered, replace the head and check also the corresponding component.
Inspecting the timing system components
- Check that the guide shoe and the tensioner shoe
are not worn out.
- Check that the crankshaft pinion and the cam-
shaft timing gear and crankshaft pinion exhibit no
wear.
In case of wear of the sliding blocks, replace them.
In case of wear of the chain or rim, replace the en-
tire unit.
N.B.
IF THE CHAIN HAS DAMAGED THE PINION, REPLACE THE CRANKSHAFT AS DESCRIBED IN
CHAPTER CRANKCASE AND CRANKSHAFT.
- Remove the centre screw with the washer and
the tensioner spring. Check that the one-way
mechanism is not worn.
- Check the condition of the tensioner spring.
- If examples of wear are found, replace the whole
assembly.
Engine
Nexus 500 euro 3
ENG - 146