Nitpicking apart, the video is of a 996K, not an 1140K or KX. Different beast (but undoubtedly still a beast).
2cvandy if your Dad used a KX for pre family transport, I suspect you are at least as old as me, so I think we'll see who lasts longest!

If I could work out how to put a photo on here, you could see my bike attached to a chair back in the '60s. If you visit my little site, it has a page for the KX, although it is a work in progress, along with all my other stuff. Don't wish to alienate people by putting the url up too often, but it appears in a couple of other posts I made today.
Jan-Peter has responded to my email about the site, and he is viewing it soley as a means of drawing out any unknown owners. Within the site there are various databases that contain sensitive info, and he has only been able to elicit that info by promising not to disclose it/make it public. He also doesn't want to spend time segregating the site into public/nonpublic (for which I can't blame him). Time spent renovating bikes is better time spent than bashing the keys of a laptop or whatever.
Not aware of any "UK founders" of the site, Jan-Peter is in Germany (or somewhere close by).