Quoth Peter Kohler:
>Seems my '67 Holdsworth requires a Campagnolo NR front derailleur with a
>built-in cable stop.
>
>Perchance does anyone out there have one to sell?
>
>And are these terribly uncommon? First time I've heard of it and I don't
>
>recall seeing them on eBay. This frame is built with the braze ons for this
>so I'm stuck.
If you're trying to go for "authentic" on this, you are stuck, that style of derailer is pretty scarce. I believe Campagnolo was the one who pioneered the housingless front setup, and did it pretty early on.
I get inquiries about this a lot from folks who are trying to upgrade riders (often UO-8s with busted Simplices) so I have prepared the following boilerplate answer to this FAQ:
The easiest solution is to just run the cable underneath the bottom bracket, as is done on most modern bikes. This will let you use any modern front derailer that is compatible with your chainring sizes.
If you're worried about damaging the paint, you can cut a short (2-3 inches) length of cable housing to protect the bottom bracket shell. This will just "float" in the middle of the cable, with no cable stops at either end. The springiness of the housing will keep it always under a wee bit of tension, so it will stay in place even though there are no housing stops.
This technique only works for front derailer cables, since they run up between the chainstays the cable can't move too far sideways. If you try it with a rear derailer cable, it is liable to slide off to the side.
It is also not unreasonable to install an inexpensive plastic cable guide. This requires drilling and tapping a hole in the bottom bracket shell (usually 5 mm or 10-32 size.) If you do this conversion and also run the rear cable under the bottom bracket you would also need to provide a clamp-on housing stop on the underside of the right chainstay for the final loop of housing.
All the best,
Sheldon
--
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