Nor is it a “Master” conversion. All sorts of small firms, as well as amateurs, were doing this sort of thing in an attempt to ‘modernise’ old bikes at one time, usually with dreadful, and ugly results. Bentley and Draper’s efforts were perhaps the best, and ‘Smokey’ Dawson of DMW Motorcycle fame was another. The Scott Three in the NMM has one of his plunger conversions. My late brother-in-law Doug Wright had a Scott with Benelli rear suspension grafted onto it, or at least that is what he said it was.
I briefly owned a 1939 Clubman Special springer at one time, and the conversion was amazingly heavy, with big phosphor-bronze castings in it. Doug also had a 1932 single downtube Flying Squirrel Sports, ex-Jack Dodds, that had a ‘Clamil’ sprung hub in it. I owned that bike later, and the hub worked quite well, but again it was ugly and heavy. At least it didn’t mean mutilating the Scott frame.