Why you ask ?
I have an idea to use a ball bearing in the clutch arm shaft of a pedal set to prevent the wear that occurs with the bushing bearings. Half of the ones I see have worn through the bearing and into the arm. Have to weld the hole and file round again. The other problem is the shafts get rusted internally making the bearings sloppy. New ones are about $65 from Porsche and are NLA for 74-89 911's. 1 I figured it will be easier to make a whole new shaft by laser cutting the lever, welding it to a 14mm shaft and drill a hole for the roll pin. I found a 6mm ID, 6mm width and 19mm OD bearing. I can have the lever made to accept the bearing.
The bearing has a 525 dynamic lb axial load limit. My calculations on a 914 pedal set are that is is a 6:1 lever ratio. So if if take 40 lb to depress the clutch the bearing will see 240 lb of axial load. Later 911's have a longer lever and clutch pedal.
So can anyone with fish scale tie a rope around the clutch pedal and to the fish scale and see how much pressure it takes?
Would be nice to see if 6 conversions with bigger engines and higher pressure plates take more pressure. Also 72 and later 911's with the 915 trans.
Going to need some one to test the first prototype too.