I have been spending a lot of time cleaning the pieces of the Atala, so that we will be ready to reassemble the bicycle once the frame is ready. After reading of countless cleaning and “degreasing” techniques on the internet, I settled on soaking pieces in paint thinner, wiping them with rags, and scrubbing with a toothbrush.
The results have been good, but also a bit disappointing. Paint thinner, perhaps unsurprisingly, seems to be very good at thinning the oily buildup on the parts, but not particularly enthusiastic about dissolving it. You wouldn’t know it by looking at the solution, though, which has turned opaque black with the grime lifted from the chain.
Cleaning most of the components seems relatively straightforward, but one is particularly odd: the front derailleur.
It's a box!
This is a Campagnolo Valentino clamp-on front derailleur from the late 1960s. It’s an ingenious design: the mechanical bits are fully enclosed by a stainless housing, which I think is also the tension member. It works, but the action feels a bit gritty, possibly explaining the difficult front shifts I noticed. I think it needs to be cleaned, but I’m hesitant to disassemble it without knowing how it works, or how to put it back together.
The internet does not seem to have any advice about cleaning and lubricating fully enclosed Campagnolo Valentino front derailleurs.