Barry Clarke of the VSCC had a very interesting article published recently, about why the shaft-drive two-cylinder and four-cylinder GNs, which succeeded the famous chain-drive models, were not a successful commercial proposition.
This reminds me that the great racing motorcyclist, Noel Pope, used one of these later GNs in the 1930s for transporting his machines to Brooklands and other speed venues. He paid £2 for it, whereas the combined price of his road-racing Velocette and the long-wheelbase track Zenith he was then racing totalled £20. The GN had a roomy dickey-seat, which would more or less take a motorcycle, but its weight caused the back tyres of the solid-axle GN to shed themselves on corners. So Pope built a crude trailer.
The GN, which had been good for 50mph on its own, would pull this at 25 to 30 mph. But eventually the vee-twin air-cooled engine of the GN gave out and when it refused to do more than 30 mph without the trailer on tow, Noel exchanged it for a small hand-drill, worth a couple of pounds. . .