Before assembling the crankcase halves, calculate the shims required to obtain the correct end float of the crankshaft and gearbox shafts.
To determine the correct shim thickness proceed as follows.
Shimming the crankshaft


Add 0.30 Mm preload for crankshaft axial bearings to bed in correctly into their seats (inner rings seated inside outer ring).
Thus, we obtain: sa=la1+la2+0.30-La.
To calculate the thickness of each shim note that: sa=sa1+sa2 where "sa1" and "sa2" represent the shims for the clutch-side crankcase half 1 and the alternator-side crankcase half 2.
Considering the alignment of the shaft, this gives: sa1=la1+0.15-La/2; and finally, the second shim thickness: sa2=sa-sa1.


In addition to the above procedure, the following is a practical shimming method, providing a guide on how to calculate the crankshaft shim thickness accurately.
Install a shim of minimum thickness (1.90 Mm) on each side of the crankshaft to prevent contact between the crankshaft web and the crankcase.
Install the crankshaft and assemble the two crankcase halves.
Fit four m8 screws in the seats indicated in figure and tighten them to a torque of 19 nm (min. 17 Nm - max. 21 Nm) (sect. 3 - 3, Engine torque settings).

Place a dial gauge (c) with magnetic base on a support plate fixed to crankcase.
Bring the stylus into contact with the end of the crankshaft and set the dial gauge to zero in this position.

Place a lever (d) between crankcase and crank web of the crankshaft pushing towards dial gauge.
Note on the dial gauge the total clearance and add a preload of (0.30 Mm) plus the thickness of the shims used (1.90X2=3.8 Mm).
Divide the resulting value by two to obtain the thickness of the shim packs to be installed at either end of the crankshaft.
Note
After assembling the crankcase halves, the crankshaft should turn with some interference in the new bearings.

Shimming the gearbox shafts
The following thickness spacers are supplied as spare parts.

Shimming the gearbox selector drum
The following thickness spacers are supplied as spare parts.
Reassembly of the crankcase halves
Reassembly of the crankcase halvesChecking and adjusting timing belt tension
Note
The on-screen icons used during this procedure are explained in a table at
the end of this section.
Note
This operation, which is performed using the dds diagnosis instrument, has
the advantage that it can be carried out on
both timing belts with the engine still installed on the frame. ...
Refitting the alternator-side crankcase cover
Before the assembly make sure that the water pump unit is fitted on the
generator cover (sect. 9 - 3.3, Refitting the
water pump).
If bearing (27) has been removed, lubricate its seat with specified grease to
fit it on the generator cover (13).
Fit bearing completely in its seat and orien ...
Spark plugs replacement
Check the colour of the ceramic insulation around the central electrode:
an even, light brown colour indicates the engine is in good condition and
running at the right temperature.
Inspect the centre electrode for wear and check spark plug gap, which should be:
0.8+/-0.1 Mm.
Important
...