The latest model Minis have a different style of clutch and thus a unique slave cylinder. The cylinder mounts more vertically that horizontally and even looks a little strange! The Mini clutch slave cylinder is a vital link in the proper operation of the Mini clutch. The master cylinder feeds the slave cylinder to exert the mechanical pressure to disengage the clutch. The simple sounding process is only complicated by a worn cylinder. As the wear continues it will first probably bypass, meaning that the clutch will not stay disengaged when holding the pedal down. The next more obvious sign is when you actually see fluid leaking! The slave cylinders are easy to replace.
Bore size is 7/8"