Derbi boulevard 125 4t, Workshop Manual

Page: 125 / 182

Distance between the shoulders
55.67 ÷ 55.85 mm
- Check the diameters of both the bearings of the crankshaft in accordance with the axes and surfaces
shown in the figure. The half-shafts are classified in two categories Cat. 1 and Cat. 2 as shown the chart
below.
STANDARD DIAMETER
Specification Desc./Quantity
Class 1 28.998 ÷ 29.004
Class 2 28.004 ÷ 29.010
Inspecting the crankshaft alignment
To install the drive shaft on the support and to
measure the misalignment in the 4 points indicated
in figure.
- Check that the driving shaft cone, the tab seat,
the oil seal capacity, the toothed gear and the
threaded tangs are in good working order.
- In case of failures, replace the crankshaft.
The connecting rod head bushings cannot be re-
placed. For the same reason, the connecting rod
may not be replaced and, when cleaning the
crankshaft, be very careful that no impurities get in
through the shaft's lubrication holes.
In order to prevent damaging the connecting rod
bushings, do not attempt cleaning the lubrication
duct with compressed air.
- Make sure that the 2 caps on the crankpin are
properly fitted.
Engine
ENG - 125