The clutch is of the dry single plate type mounted in a light alloy housing which is bolted to the engine output/balancer shaft rear end. A diaphragm spring, seated on a wire ring in the housing, forces a pressure plate to clamp the friction plate firmly against the cover plate which is bolted securely to the housing. Since the friction plate is mounted on the gearbox input shaft drive is thus transmitted from the engine to the gearbox.
The release mechanism is operated by cable from the handlebar lever and acts on a pushrod, via a thrust bearing, that is situated in the gearbox input shaft. The pushrod front end is held in a pilot bearing set in the engine output shaft rear end; when the release mechanism is operated a shoulder on the pushrod forces the diaphragm spring to deform and relax the clamping force it exerts on the pressure and friction plates.
Clutch adjustment is described in Routine Maintenance - Major service.
Note that BMW recommend that the clutch be dismantled once a year so that the gearbox input shaft and clutch friction plate centre splines can be degreased, checked for wear and lubricated on reassembly. This is to preserve the clutch's smooth action and reliability.
Next Section: 2: Removal