Originally Posted by
Hondo6
I think that the GB-100 BB spindle was the version referenced by the Sheldon Brown wepbage I linked. DA 7400 didn't show up until 1984, or around a decade later. I believe that 7400 used JIS spindles, except possibly for the NJS track BBs (not sure about 7100/7200/7300).
I do not know the answer, but I have heard that '80s 7400 may have the same Campy taper as Sugino Mighty and Suntour Superbe. And that early '90s 7410 with the tiny 103mm spindle might be another example of JIS short.
But the topic of spindle taper is full of BS. Phil Wood claims Campy was JIS taper before ISO. I've measured the taper of a range of BBs directly, and the pre-ISO Campy and Mavic had the same taper as ISO, while JIS was a noticeably different taper angle. Yet every reference says they are the same angle and merely different widths.