Airone Manuals Question

Greetings for the USA.
I’ve posted this question to the GuzziSingles list on Google, but thought I’d give the forum a try as well.

I’m wondering if anyone knows of any Airone Manuals available that would specifically cover model year 1953 for the Sport.
As a brief history, per the Mario Columbo book, the Sport was introduced in 1949, rated at 13.5hp @ 6000rpm, with the 2544bis cam and manual magneto, the User, Workshop and Parts manuals for the 1949 are readily available on sites such as Then, also according to the Columbo book, in 1954’, the factory advertised numbers were 12hp @ 5200rpm no mention of cam. There are 1956’ manuals, User, Workshop and Parts, listing the cam as the new 2415 with auto advanced magneto.

I am replacing the cam in my 1954 Sport with a NOS 2544bis cam, but with only the 1949 and 1956 manuals available, the Valve and Magneto timing numbers are wildly different, 1949’ 95-105mm Valves and 78-85mm Magneto, while the 1956 numbers are 55mm Valves and 20-21mm Magneto. There is a Parts manual for the 1953 Sport, which list it as using the 2544bis cam, with auto advance Magneto, but I can not lay my hands on a User or Workshop manual, so I would love to find the timing numbers for the 1953, seems like it must exist in someone collection.

Baring that discovery, I’m tempted to time the vales to the 1949 spec. and the Magneto to the 1956’ spec. Any thoughts appreciated.

Many thanks,
Mike Peavey
Boston, Massachusetts