Herse et al. outsourced the forging. Maybe to TA? But there were tons of makers of cars and bicycles in Levallois, so the suppliers probably existed. Also, they had the money in the late 1940s when business was good to order a large batch. I wouldn't be surprised if Herse ordered all his cranks at once. Maybe a 1000? The style later changed a bit (1960s?), so they may have run out then and ordered a new run? All this is speculation. Anybody on the list who can read Japanese? I suspect the info is in the Herse book. Please contact me, and we can talk about translating or summarizing part of the info.
Numbers of bikes are small, but not that small, but Singer has made, so far, 3200+ bikes since 1938...
Wheels in the trials: After the war, tires were not included in the weight. The reasoning was that lightweight, handmade clinchers were not yet available again, and the heavy tires would skew the comparisons with the pre-war results. Wheels were, as far as I know. Before the war, it was the entire bike that was weighed (as in the figure quoted for Herse's Narcisse). More research will shed more light onto all this. I am working on it, with Joel's help. It'll be in the newsletter... Including photos showing the bikes being weighed. We'll see whether they had tires installed or not!
Jan Heine, Seattle