Scooter Fly 50 4t 4v, Workshop Manual

Page: 21 / 208

To install the crankshaft on the support and to
measure the misalignment in the 4 points indicated
in figure.
N.B.
IF VALUES OTHER THAN THOSE ALLOWED ARE DETEC-
TED, TRY STRAIGHTENING THE CRANKSHAFT BY IN-
SERTING A WOODEN WEDGE BETWEEN THE HALF
SHAFTS OR BY CLOSING THEM WITH A VICE AS NEE-
DED. IF EVEN AFTER THIS OPERATION THE VALUES ARE
NOT THOSE ADMITTED, REPLACE THE CRANKSHAFT.
Characteristic
Off-line maximum admitted - A
0.15 mm
Off-line maximum admitted - B
0.02 mm
Off-line maximum admitted - C
0.02 mm
Off-line maximum admitted - D
0.10 mm
- Using a bore gauge, measure the connecting rod
small end diameter.
N.B.
IF THE CONNECTING ROD SMALL END DIAMETER EX-
CEEDS THE STANDARD DIAMETER, EXHIBITS WEAR OR
OVERHEATING, PROCEED TO REPLACE THE CRANK-
SHAFT AS DESCRIBED IN THE CRANKCASE AND
CRANKSHAFT CHAPTER.
Characteristic
Rod small end diameter
13 +0.015 + 0.025 mm
Max. diameter admitted: check the small end
13.030 mm
Calculate the coupling clearance between pin and rod small end
Characteristic
Pin - connecting rod clearance
0.015 - 0.029 mm
Cylinder Head
Before performing head service operations, thoroughly clean all coupling surfaces. Note the position of
the springs and the valves so as not to change the original position during refitting
Fly 50 4t 4v
Characteristics
CHAR - 21