I've just found this thread and must say Dougy that you are the leading candidate for the cool Dad award. It's been fascinating reading my way through this thread and seeing the way you can shape and weld metal. That diesel HD is just sooooooo cool, - your daughter is a very lucky girl. My doctor won't let me ride motorcycles anymore, but if I still could I think I'd be looking at building myself a diesel bike too.
It was very interesting to see just how much paperwork, inspecting and rubber stamping was involved in getting your son's bike on the road. Here in New Zealand it's still relatively painless to register a motorised bicycle. IC engined machines have to be registered as a moped which is not complicated at all and only involves filling out a form with all the right details on it, paying fee and being given your numberplate. So far electric powered machines don't seem to need registration. I've been riding my old Hercules trike that I converted to electric propulsion around town here for a few years now and the local Police guys and girls just smile and wave whenever I go past. I do have a totally out of date brown and white motorcycle plate from the 1930s on the back of my Hercules though which often raises a smile as well.
That CG Honda engine should work out well for you. I rode the CB version as my going to work bike for some years when I was in my 20s and it was totally reliable.
i love the old French motorcycle frame and forks, it should clean and straighten up into a really nice looking bike.
Money can't buy happiness, but it can buy chocolate which is almost the same thing
Home of the Kotanga Tramway.