Release levers (46) of a clutch are provided with wear-resisting pads (54) of porcelain, ceramics or sintered material for engaging a release thrust bearing. The clutch may include two friction discs (20, 22) with porcelain facings for connecting a drive housing to concentric output shafts, each disc cooperating with a respective presser plate operable by respective levers fitted with pads as above. Alternatively, both discs may transmit the drive to a single output shaft. <IMAGE>
