Great looking Swordfish Bruce.
The Swordfish was launched in 1950, and according to the brochure, it was the same as the Britannia but with a few extra bits - basically the delux version. The Swordfish had advance and retard plus a water pump cooling system and came in a choice of three colours:- light green, cambridge blue or sky blue.
Of the Swordfish I've seen, all have had Wico Pacy ignition, although an instruction book does state Villiers was also used.
I have a Mk3 (tank same colour as Mk4) which has the solid head cylinders, and a Mk4 which has detachable cylinder heads - photo below. Production ceased in 1957.
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