just before writing this Contri, I studied closely the detailed photos that the seller provided on Ebay, as I tried to decipher the frame No on the near-side rear drop, so that I could check it against the frame I have in store.
It seems quite clear that this bike is genuinely a 1930s machine, as the brakes bars stem gear, wing-nuts etc are all from that period. The Super Champion gear is a three-speed but is it an 1/8" chain or a 3/32" as both were available at various times.?The 3/32 x 3-speed chain model ceased production in 1938.
The tension arm on Martin's new acquisition does not have the hook for the detentioning wire control. This feature was introduced in 1937, so it is likely that gear is a 1936 Type Competition model. If this is the case the tension arm would carry the logo Super Champion printed in block capital letters rather than the later style cursive script.
No Super Champion gear of this "osgear" type had a toothed roller. I think in the instance of this particular gear, the roller has just gradually been worn away by the chain, resulting in notches being formed; after all the bike could well be 70 years old.
All this investigation has been made reconsider my own Automoto frame that so closely resembles Martin's. I would never have that that it was a 30s frame, but, just like my original, probably 1935 Reyhand, and my original 1936 Alcyon Tour-de-France. also equipped with an Osgear, the Automoto has just one single D/T transfer, aquite a small copy of the distinctive trade mark, in silver, and this sits midway down the tube on the upper surface.
Norris Lockley, Settle UK