Joined: Aug 2010
Posts: 12,727
Likes: 2,105
From: Madison, WI
Bikes: 1961 Ideor, 1966 Perfekt 3 Speed AB Hub, 1994 Bridgestone MB-6, 2006 Airnimal Joey, 2009 Thorn Sherpa, 2013 Thorn Nomad MkII, 2015 VO Pass Hunter, 2017 Lynskey Backroad, 2017 Raleigh Gran Prix, 1980s Bianchi Mixte on a trainer. Others are now gone.
That is a neat bike you have, looks like half step gearing.
Not sure if you are trying for a period restoration or for a bike that you want to ride with more modern components.
As an example, in the photo I have a 1961 or 62 bike that the handlebars did not work for me, they were really narrow and I did not like the shape. I put on a threadless to quill adapter, threadless stem, modern bars, modern brake levers and I like to also have interrupter brake levers too. Many parts are still original like the campy downtube friction shifters and Mafac centerpull brakes.
I am not saying you need to go modern if you do not want to, but you are starting from scratch so you could be as creative as you want to be. I did not discard the old parts, I could restore it if I wanted to later.
On one bike I have 25.4 bars with a 26.0 stem, I found that three layers of aluminum from a beer can was the perfect shim. But I do not know if different cans had identical thickness or not, I used a caliper to measure thickness. It is best to not try 25.4 bars on a 26 stem with no shim.