I learned from Max that the 22.2 in metric translates into 81.When I Googled the 22.2mm to inches it came up .87. I have found the French 97's that are 24.6 and the 48's which are 26.2. Our fond friend Bruce Lancaster got that 24.6 from me a few yrs ago. The 24.6 are even rarer ,seen 1 other in last few yrs.Lots of 26.2's as they were military with a governor .Each carburetor also had a serial number stamped on the flat raised area of the bowl .Last pic shows the side of the bowl detail.FYI,Embossed on the side of the bowl under Zenith/Stromberg is this and below that "fabrique en France" (made in France)
Breveté SGDG
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Breveté SGDG on an Ariston music player
Breveté SGDG was a
French type of
patent that ceased to exist in 1968. The name was a common abbreviation for
"Breveté Sans Garantie Du Gouvernement“ (patent without government guarantees).
Background
France and Belgium maintained a system of simple registration of patents. It was believed that patents registered in this way are free from any liability from the government perspective.
In France, the law of 1844 states that patents are issued
"without prior examination, at the risk of the applicant and with no guarantee of function, novelty and merit of the invention also in terms of precision or accuracy of the description".
[1][2][3][4]
In Belgium, a similar regulation was in place in article 22 of the 1984 Patents Act,
[5] and, as of 2019, is still in place.
[6]