This is a partial reprint of an article that appeared in the August 1939 edition of the popular magazine 'Motor Cycling' as mentioned earlier, a certain Lieut B. D. S Ginn entered MCC events in a BSA specially modified to drive the rear wheel, this was achieved by taking the drive from the gear-box main-shaft nose (where the speedo drive usualy lives) and, using chain and sprocket, driving a shaft that ran the length of the trike to a bevel-box (ex Morgan!) which in turn drove the rear wheel via another chain and sprocket. These modifications are well illustrated here, the bevel-box even included a free-wheel assembly to allow the rear wheel to be on overrun until the front ones spinned, to prevent any unnecessary wear the chains were removed between observed sections

A pretty poor 'photo of B.S.Ginn, but it is the only one we have, it shows him taking part in an MCC trial, sometime in the thirties

Here is a view of the front-end mechanics, showing the power take off from the forward end of the gear box main-shaft to the special drive shaft that runs the length of the car

This shows the method of taking the drive from the driven shaft to the rear wheel via a Morgan bevel box and two sprockets

Here we see a general view of the modifications to the three-wheeler