I have been in touch today with Wood Auto about this leccy foot for the Norton.
I outlined the situation and talked to one of the engineers in the offices by phone.
The item in discussion is called a 'Dynastart' and they do manufacture one. It is about the size of the old dynamo's from 'A' series engines and is currently used on some road laying vehicles. He described the ones that are used for flattening out tarmac, they have a small diesel engine and are usually walked behind. They have a belt drive to drive and start the engine but the output shaft can be modified to any specific design. Starting rotation can be either clock or anticlockwise and mounting in a cradle or bracketted. The motor is as usual exited to drive the rotor and once the engine starts the same rotor then becomes the dynamo.
I would have liked to meet the guy in question and actually see one of these items but could not sway it, but for a one off intro I felt that the discussion was quite promising.
He did ask me to get in touch with you (Bruce) and pass on his mail address :- lee.brook@woodauto.co.uk as he wants to discuss with you in person your requirements and dimensions.
I could also go there again and try and get some pics if necessary.
Hope this helps Bruce.
Cheers SteveD