Greenwood's 'sidecar' at its prime

Thanks to an observant reader I was sent over these great pictures of Owen Greenwood's infamous 'sidecar' creation. They are all pictures I never saw before and I quite like them. It also struck to me that the 'four-wheeled motorbike', as the thing was named soon after it entered the sidecar championship in 1965, appears to be road registered at one point. I can't find anything on '139 GYN' though. What's more: I don't think that is Owen Greenwood at the wheel, but who is it then? And how about the lady passengers? 

Anything goes: 1960s paddock scene includes a clever piece of British engineering

Mind that aluminum body… Greenwood Special weighed just over 300kgs

Mini sidecar became the terror of the tracks in the mid-1960s, pulverizing the championship

Oops! Things didn't go well all the time though. Double rear wheels can be seen here