Here's a few more picts. Lloyd's made the Quadrant bike. They also made engines, including a 624cc single cylinder. My grandfather brought one back by ship in the 40's, it was a 1899 or 1900. I still have it, but the frame was smashed in an accident, the gear box is still intact. But since the shaft makes up the rear part of the bike, I have never done anything with it, still in my grandmother's attic. Would be interesting to see the same design work on the left hand side. It is a very simple system. They used to advertise it as a solution for not soiling the pants or dress with mud, which chain drives would do. Of course they also didn't think of chain guards back then either, lol. I could see a larger sprocket mounted to the clutch bell, that interlocks with the shaft gears, the shaft could then run back to a sprocket on the wheel. Could be done easily. You wouldn't need a gear reduction box if you do the ratios right, I think. Enjoy!
Hmm on second thought you would need a reduction small gear to the larger gear, but then you wouldn't go to a small sprocket for a chain, just a same size sprocket to the shaft. I'd like to see a mod on a G4, where the small chain sprocket could be replaced with the shaft drive. Keep the ideas floating. I hate chains!!!