Inspection Of Platinum Points And Contact Plate

Remove the protecting cover {Fig. 1) and check the gap of the two points, which must be 0.4 mm.

To adjust said gap, turn the screw shown by the arrow (Fig. 3). Remember that the adjustment of one pair of points is independent of the other couple.

At the upper dead centre, the platinum points must be at the initial phase of their gap. Looking at the engine, on the starter side, the driving shaft rotates clockwise.

In order to render the adjustment easy, it is necessary to have a 12 V lamp, connected by means of a wire to the terminals of the points which are being adjusted, and the other to earth (Fig. 2). Then proceed as follows:

1) Remove the cover on the starter side.

2) Connect the R.H. platinum point (looking at the contact breaker) t6 the lamp.

3) Insert the ignition key situated on the headlamp.

4) Rotate the driving shaft clockwise (looking at it on the starter side) till the letters PM (= DEAD CENTRE) appearing on the pulley coincide with the mark stamped on the crankcase (see Fig. 47); at this moment, the lamp must light up. If the lamp should light up before or after the moment when the two reference marks coincide, slacken the three screws which fix the contact plate (see Fig. 1), rotate either clockwise or anticlockwise, according to the necessity of retarding or advancing the engine, then tighten up the screws.

N.B. - If it is required to check the initial opening of the platinum points, using an external battery (that is to say a battery that is not connected to the lighting system), it will be necessary to go through the above operations once again, without inserting the ignition key situated on the headlamp. When the reference marks coincide, the lamp will go out. Go through the same operations for the couple of platinum points on the L.H. side. If, after checking the left point, the lamp light should not go out exactly when the two marks

coincide, adjust the support of this point, by slackening the two screws that secure said support to the plate (see Fig. 3, N. 2) then turn the eccentric screw (Fig. 3, N. 1) and rotate the support to advance or retard till it reaches the exact position.


To perform this operation it is necessary to remove the side cover. Then unscrew the nut on the driving shaft, using a 32mm spanner, and remove the oil pump pinion (Fig. 4). Please note that both on the shaft and the pinion two reference marks are clearly visible. When positioning the pinion, the two marks must line up. When positioning the gear of the oil pump, ascertain that its mark coincides with the mark that appears on the driving pinion (see Fig. 10). When inspecting the clutch, remove the chain adjuster pin (Fig. 5), and — at the same time — detach from both shafts the driving pinion and the chain sprocket (Fig. 6).

Use a 10 mm spanner and take away the bolts which position the six springs (Fig. 7) and remove the spring plate. Inspect the surface of the disks with friction washers and, if wear is evident, discard them and replace them with new ones. If the springs reveal signs of wear, they should be replaced. If the clutch is blocked, check the sliding of the key within its slit. In the event that the clutch, although being free, keeps operating the gear shaft, check if the bush slides properly on the shaft.

When assembling the clutch, follow the instructions described for dismantling in reverse, keeping in mind the correct arrangement of the plates (Fig. 8).

In order to carry out all the operations connected with said assembly, the key must be positioned on the shaft horizontally (Fig. 9). After assembling the plates, springs, and springs plate connect the clutch drive and adjust the lever to release said plates, so that the teeth are properly aligned. Position the clutch bell and, at the same time, pull the clutch lever to allow the proper assembly of all plates inside the bell. Then release the lever before withdrawing the bell. Position said bell, after replacing the main drive chain on it, together with the driving pinion (see Fig. 6).

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