Yep, fun detail. They stopped drilling them for the Sport cambio early on, like 1960, but kept using the same forging dies with the "land" for the hole, for a long time. Seeing it in 1971 is surprising, but Jackson may have bought a tonne of dropouts and took years to use them up?

My '58 Follis came with Campy dropouts and would have had the drilled spring hole for sure, only someone drewed it to put a Huret Allvit on it! How's that for a dumb move? I lucked into the Campy replacement hanger, part number 80/1 I believe, that had the hole for a Sport, weird that a part like that lasted all those decades without getting used. So anyway, my Follis dropout is now whole, with hole!

I even needed the hole, because the mech I'm using on that bike is a hybrid of a Sport and a Record, with the sprung upper pivot off the Sport, which vastly increases the gear range I can get compared to a Record or Gran Sport.

So now I have a wide-range triple in front, and a 14-30 freewheel, lower than 1:1 low gear, hard to get with a vintage Campy racing mech. Nice for fat old guys.



The "claw" hanger is only attached to the cambio to keep all the parts together, obviously it gets removed to mount it on a dropout with integral hanger.
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