It turns over smoothly by hand, but just won't fire up.... can anyone spot anything wrong from the pic?
Dunno. To be honest, I think the previous owner has used lots of non genuine parts. And plumbed the carb to the heat exchangers... On à plus side, not a spot of rust to be seen!
When it starts you will probably need a welded fan to survive having such a large crank pulley, but it will probably slip as you have missed out the Woodruff key. But mine in the same condition has never managed to start either and so it has survived years and zero miles. I dont even remember when I changed the oil or the spark plugs.