Gilera 633721 Workshop Manual page 166

Engine
Splitting the crankcase halves
- Remove the engine support retain screw on the
flywheel side half-crankcase.
- Remove the 14 crankcase coupling screws.
N.B.
THE FASTENING SCREWS ARE OF 3 DIFFERENT
LENGTHS. NOTE THEIR CORRECT POSITION.
- Split the crankcases while keeping the crankshaft
inserted on the flywheel side half-crankcase.
- Remove the coupling gasket.
N.B.
THE BUSHING SUPPORT CAN BE LEFT IN THE FLY-
WHEEL SIDE HALF-CRANKCASE.
Removing the crankshaft
- Before removing the crankshaft, check the timing
with the countershaft. To carry out this check, turn
the crankshaft to align the two holes obtained on
the crankshaft with the hole on the countershaft
control gear.
This is an optimal position also to remove the
crankshaft.
ENG - 166
Nexus 500 euro 3