APRILIA PEGASO 650 STRADA, Service Station Manual

Page: 134 / 236

10.With a gauge, measure the valve seat width
again. If the measurement is not within the
values previously specified, reface and lap
the valve seat.
VALVE SPRINGS CHECK
CAUTION
THE FOLLOWING PROCEDURE APPLIES TO ALL VALVES
AND VALVE SEATS.
•
Use a gauge to measure the unloaded
valve spring length. If the length meas-
ured is not within the specified values,
replace the valve spring.
Unloaded valve spring length:
•
Inlet: 40.38 mm (1.59 in); Maximum
limit: 38.36 mm (1.51 in)
•
Outlet: 40.38 mm (1.59 in); Maximum
limit: 38.36 mm (1.51 in)
With a dynamometer, measure the compressed
spring strength, with fitted spring length 35.00 mm
(1.38 in). If the length measured is not within the
specified values, replace the valve spring.
Compressed valve spring strength (fitted):
171 / 197 N at 35.00 mm (17.44 / 20.09 Kg at
35.00 mm) (38.44 / 44.29 lb at 1.38 in).
•
On a contrasting surface, use a square
to measure the valve spring angle (H).
If the length measured is not within the
specified values, replace the valve
spring.
Checking the cylinder head
•
Using a round scraper, clean off any carbon deposits in the combustion chamber.
CAUTION
DO NOT USE A POINTED INSTRUMENT TO AVOID DAMAGING OR SCRATCHING THE SPARK
PLUG THREADS OR THE VALVE SEATS.
•
Check the head for damage or scratches and replace it if necessary.
•
Check there are no mineral deposits or rust in the head water cooled jacket; clean off if
required.
Engine
PEGASO 650 STRADA - TRAIL - FACTORY
ENG - 134