Derbi BOULEVARD 50 2T, Workshop Manual

Page: 82 / 154

Inspecting the cylinder
- Check that the cylinder does not show seizures.
Otherwise, replace it or adjust it respecting the al-
lowable increases
- Measure the internal diameter of the cylinder with
a bore meter, according to the directions given in
the figure
- Check that the fitting surface with the head is not
dented or distorted.
To classify the cylinder-piston fitting, check the ap-
propriate table
See also
Cylinder - piston assy.
Inspecting the piston rings
- Alternatively insert the two sealing rings in the
cylinder
Using the piston, insert the seals perpendicularly
to the cylinder axis.
- Measure the opening of the sealing rings using a
thickness gauge as shown in the photograph
- If the values are higher than the values prescri-
bed in the chart, substitute the rings
Removing the piston
- Position the snap ring in detail 1 with the opening straddling the arrow printed on the tool.
-Push detail 2 into detail 1 until the stop and extract detail 2.
- Insert detail 3 into detail 1, position the assembly in the snap ring assembly area, and push detail 3
all the way in.
N.B.
REFIT THE REMAINING PARTS FOLLOWING THE OPERATIONS IN REVERSE ORDER FROM
THE REMOVAL OPERATIONS
Specific tooling
020166Y Pin lock fitting tool
Locking torques (N*m)
Locking head nuts: 10 to 11 N·m
Engine
ENG - 82