The clutch is lubricated with oil from the same passage as the transmission. After the crankshaft, pistons, rods, camchain, cams, and transmission gears and bearings are lubed, what's left goes to the interior of the wet clutch via the clutch oil restriction jet and through the pushrod passage to the interior of the clutch inner hub. Some of the oil in the inner hub is used to lubricate the sliding surfaces of the clutch booster. The remaining oil then flows through holes in the inner hub to lubricate the friction disks and the sliding surfaces of the clutch. After which the oil is flung out of the clutch to drain into the oil sump for pickup and return to the oil tank by the oil scavenger pump. BTW, the clutch oil jet is listed in the "Scheduled Maintenance" to be removed and cleaned every 15,000 km. Doing this every oil change is an even better idea, especially if your clutch gets hard use.