Checking The Rocker Arms - APRILIA ETX 150 Service Station Manual

ETX - STX 150
•
Check that the camshaft gear works properly: if it is damaged or does not move smoothly,
replace the timing chain and the camshaft gear.
CAMSHAFT LOBES
•
Check that they do not show blue colouring, cracks or scratches; otherwise, replace the
camshaft, gear and chain.

Checking the rocker arms

•
Check that the bolt surface that con-
tacts the rockers is not exceedingly
worn.
•
Check the rocker to valve and rocker to
rod contact surfaces.
Inspecting the valve housings
•
Check that the valve guide does not show any signs of wear and is within the indicated
values; otherwise, replace the component.
Characteristic
Intake guide - standard diameter
5.485 / 5.475 mm (0.2159 / 0.2155 in)
Intake guide - Wear limit
0.01 / 0.04 mm (0.00039 / 0.00157 in)
Discharge guide - standard diameter
5.485 / 5.475 mm (0.2159 / 0.2155 in)
Discharge guide - Wear limit
0.01 / 0.04 mm (0.00039 / 0.00157 in)
Engine
ENG - 97