Now we know the secret. You have a full to the brim computer memory! I don't trust computers that much. I've had one hard drive fail and I never want to go through that again. I've taken various back up precautions since then but from friends tales of woe it seems that no matter what you do you never quite get back everything.
Back to interesting things. No, I have very little photographic eveidence of Frank Fletchers rides in the ISDT. He was a private entrant with no affiliations. When you look at ISDT reports there are lots of photos of National teams, factory teams, Services teams, club teams and so on but not much of solo private entrants. They are occasionally seen in the back ground or as part of a group on a stiff hill or through a watersplash or some such but you have to hunt for them. I've found a few of that sort showing Frank but nothing good enough to show how he prepared the bike. I also contacted the Technische Museum Wien, who hold much of the official German photographs taken at the 1939 ISDT but they have none of him. Possibly I could contact Mortons to see what they have but that could be an expensive exercise and I'd rather save that one until my next trip to England and do it in person. Much more fun.
Of course the 9D Villiers engine itself has an excellent ISDT record even though the British didn't like them much. The Dutch Eysink team did very well with them both before and after WWII. I'd be very interested to know how they prepared their bikes.
I'm sorry this seems to be getting away from WD bikes but it does involve general proprietary items used across a range of machinery as well as in the WD field. In fact you could say they are regular civilian items successfully adapted for WD use.