I have just gone through the OHC Four despatch books again and the earliest machine I can find with "Green and chrome finish) went out on 15.11.35 so was a 1936 model year (export) machine. I may, of course, have missed an earlier example of a green cammy but I don't think so.
I have also checked the 500 singles books for late 1935 model year and early 1936 model year with the result that the first green VG machines (export) appear in October 1935 as early examples of 1936 model year production.
So it seems that the green finish may first have appeared at the beginning of the 1936 model year. This would be logical because it was the time of a major change in Ariel production with the elimination of the "Standard" models. These 1935 models were the last models produced without the chrome tank and with steel primary chaincases instead of the more familiar later alloy ones. Also new for 1936 was the large diameter clutch - the one which then went right through to the end of 4-stroke production. The steering head bearings changed and the rear brake plate became anchored by a brake arm rather then the old peg in the rear fork which engaged in the brake plate. Most certainly, there should also have been the 1000cc Square Four at the top of the range but for reasons I still cannot tie down, the 600cc OHC engined Four was produced for another year - with the old Y frame instead of the modernised F frame.
I conclude that the green finish, in all probability, was introduced for the 1936 model year.
Paul Jameson
34 OHC 4F 600 (project), 35 LG 250, 37 RH500, 52 ex ISDT KHA, 54 KH(A), 75 Healey 1000/4.
Former Machine Registrar & Archivist, General Secretary and Single Spares Organiser (over a 25 year period).
Now Archivist (but not Machine Registrar), Gauges and Clocks Spares Organiser.