After reading the Weinmann thread, I was struck by the lack of similarity between brakes and rims. The critical skill for making brakes seems different than the critical skill needed for making rims. One seems to be about forging, and another about extruding.
In the case of Cinelli, you have the forging operation for the stems, and in the early days, the hubs; the metal bending operation for the handlebars, the frame shop; and then the saddle making operation. Maybe it's me, but I do not see much synergy there. Why would a company with Cinelli's place in the market in the 60's and 70's start making plastic saddles?
The other question becomes why didn't Campagnolo make bikes? It can't be that Campy was worried that its customers (other builders) would not want to become its competitors. Campagnolo's position in the market was too strong. The other builders would have had to use Campy parts anyway. Remember that Cinelli was strong enough to make frames without worrying that other framebuilders would boycot their stems and bars. Surely if Tullio had said I am opening a frame shop, I will hold auditions in Vicenza next week, he would have had no shortage of applicants.
Just a thought,
Marcus Helman
Huntington Woods, MI