Originally Posted by jebensch
" ... if you break off the tab to insert the pad, wouldn't you have to make doubly-sure that you have the end WITH the tab facing correctly with the corresponding wheel rotation - or I'd think the spin would slowly remove the pad for you. Messy. Could be wrong though.
Very true! However, there were literally decades
holders were simply produced with one end left open. The idea of closed holders was really a more recent evolution. I never heard of any accidents from classic Campy or Mafac holders being installed the reverse of how they should be placed... but perhaps a personal injury law suit (in California, no doubt) had inspired manufacturers to modify the designs.
There was a period from the late 70s to mid 1980s when Shimano's holders were all fairly simple, and still had a tall profile, but were not made for replaceable pads. I wonder whether competition from after-market brake pad companies (such as Kool-Stop) which began making reusable holders for their own pads had gradually prompted the folks like Shimano to make re-usable holders and
their own replacement pads, too.
By the late 1980s, the rather modern style holders for my Dura-Ace 7400 brakes had an open end... a decade later, the still similar Shimano holders (and copies from Tektro, etc.) had begun using small set-screws to hold the pads. Perhaps there was a greater issue with the slimmer profile rubber pad holders losing the pads? - On these more streamlined holders it is truly less evident at a glance which end is actually the open side.
I suspect the most simple style of closed holders for earlier brakes were just intended to force the consumer to buy a more expensive complete replacement pad & holder set. For example, the early 1970s Weinmann holders
were all open, and inexpensive insert pads were common in any bike shop... but, by the late 70s their holders were closed and of their replacement rubber pads alone were already becoming difficult to find. There was also an interim variant (which I mainly remember seeing on juvenile bikes from Schwinn) which had a "safety sleeve"
to prevent the pads from ever pulling out if anyone had placed them incorrectly on a caliper... but I wonder if this had ever been a realistic concern. Or, was this just another example of overprotective CPSC or Schwinn paranoia?
It would be very interesting to conclusively trace the actual chronology of it all... even within a single manufacturer's designs.