I gave Little Willie a check over a short time ago and it seems the problem I mentioned earlier may have been fuel evaporating in the feed pipe or not enough oil in the petrol (I filled up this afternoon). To me it seems the piston nipped up. I've added a bit more oil and started the bike, and it's been running quite happily for twenty minutes or so. It's either fuel problems or maybe another occurrence of my condenser acting up. Perhaps I'll buy a new one!
I've been the proud owner of a 1965 BSA Bantam D7 since 1991, affectionately known as Little Willie (Wilhelmina) and love to take her out for a ride so that others can see her.