Clutch assembly: clutch

6.1 -

3	Clutch spring

4	Pressure plate

Bearing

Circlips

Nut

8	Belleville washer

9	Clutch plates

10	Belleville washer

Flat ring

12	Clutch centre

Spacer

14	Clutch lifter

Spare parts catalogue


1200 ABS	Clutch
1200 S ABS	Clutch

Important

Bold reference numbers in this section identify parts not shown in the figures alongside the text, but which can be found in the exploded view diagram.

Description of the clutch assembly

The clutch is disengaged by a drive unit consisting of a thrust piston (C) accommodated inside a small cap mounted to the generator cover. This piston (C) pushes a pushrod (B), which runs through gearbox primary shaft and operates the pressure plate (4) located on top of the clutch plate pack (9).

Drive is transmitted from the crankshaft to the gearbox primary shaft by a gear integrated with the clutch housing/primary drive gear pair (A).

Accommodated in the clutch housing is a set of drive and driven plates (9). When the clutch is operated, the driven plates push away a drum (12) which is splined onto the gearbox primary shaft.

Before working on the internal clutch parts, check that the clutch operates correctly. Then deal with the problem in a systematic manner.

The following is a list of possible causes of clutch malfunctions.

A clutch which does not disengage may be caused by:

-	excessive play of the control lever;

-	distorted clutch plates;

-	incorrect spring tension;

-	faulty clutch release mechanism;

-	excessive wear of the hub or clutch drum.

A clutch which slips may be caused by:

-	insufficient play of the control lever;

-	worn clutch plates;

-	weakened springs;

-	faulty clutch release mechanism;

-	excessive wear of the hub or clutch drum.

A noisy clutch may be caused by:

-	excessive backlash between the primary drive gears;

-	damaged primary drive gear teeth;

-	excessive play between friction plate tabs and the clutch drum;

-	worn gear/clutch drum bearings;

-	the presence of metal particles (filings) on the gear teeth.

Removal of the clutch


Operation	Section reference
Remove the undersump assembly	5 - 4, Removing the undersump
Drain the engine oil	4 - 3, Changing the engine oil and filter cartridge
Remove the clutch cover	9 - 6.2, Removal of the clutch-side crankcase cover

Note

For clarity, the figures show the engine removed from the frame.

Undo the fixing screws (1) and remove the ring (2) and the springs (3) from the pressure plate (4).

Slide the pressure plate (4) paying attention to the circlips (6).

Remove the clutch control pin (14) and the bearing (5).

Restrain the clutch centre (12) using service tool 88713.3408 and remove the centre nut (7).

Remove the Belleville spring (8), slide the clutch drum (12) and remove the series of discs (9) from the clutch bell.

When removing the discs (9), keep them paired in the assembly order and set them aside tied together, if necessary.

Slide the spacer (13).

Withdraw the Belleville washer (10) and flat ring (11) from the clutch centre (12).

Checking and overhauling the components

Clearance between the clutch drum and friction plates

Insert a friction plate (E) in the clutch drum (F) and measure the clearance (S) with a feeler gauge.

Clearance “S” must not exceed 0.6 mm.

If it does, renew the plates and, if necessary, the clutch drum.

Overhaul of the clutch plates

The clutch plates must not show any signs of blackening, grooves or deformation.

Measure the thickness of the friction plates. it should not be less than 2.6 mm.

Important

The total thickness of the discs pack must not be less than 46.1 mm.

Place the plate on a flat surface and check the amount of deformation with a feeler gauge.

Max. flatness error: 0.2 mm.

Overhaul of the pressure plate

Check bearing (5) condition. renew the bearing if the play is excessive.

Check the contact surfaces of the last friction plate; if extremely scored, polish it in the same manner as described previously for the cylinder head surface (Sect. 9 - 4.5, Overhaul of cylinder head components).

Check conditions of the spring guide bucket tappet (G) of the pressure plate (4) and of the circlips (6).

Overhauling the pressure plate springs

Measure the length “L” of each spring (3).

Minimum length: 41 mm.

Renew any springs that are shorter than the above limit value.

Reassembling the clutch

Position the spacer (13).

Fit the flat ring (11) and the Belleville washer (10) on the clutch drum (12), so that the convex side faces the clutch drum.

Locate the Belleville washer (8).

Install the clutch plates (9) in the following order:

on the drum (12):

-	a series of ten driving discs (L) alternately to new driven discs (I) thickness 2 mm;

on the pressure plate (4):

-	one driven disc (H), 2 mm thick;

-	a driving disc (L).

Apply the prescribed grease to the thread of the gearbox primary shaft and the mating surface of nut (7), and fit it over Belleville washer (8).

Lock the clutch center by means of tool number 88713.3408 and tighten the retaining nut (7) to a torque of 190 Nm
(Min. 180 Nm - Max. 200 Nm) (Sect. 3 - 3, Engine torque settings).

Insert the control pin (14) in the bearing (5) and the latter in the gearbox primary shaft.

Place the pusher plate (4) with the two discs on the centring tool part no. 88713.3352.

Fit the pressure plate (4).

Insert a spring (3) in each slot.

Position the O-ring (2).

Lubricate the thread of the screws (1) with oil.

Insert the screws (1).

Tighten the screws (1) to a torque of 10 Nm (Min. 9 Nm - Max. 11 Nm) (Sect. 3 - 3, Engine torque settings).


Operation	Section reference
Refit the clutch cover	9 - 6.2, Refitting the clutch-side crankcase cover
Top up the engine oil	4 - 3, Changing the engine oil and filter cartridge
Refit the oil sump guard unit	5 - 4, Refitting the undersump