Ha..the age old A series starting probs.
I spent thousands on a host of NOS parts from the US recently on my A7SS. Did a lot of advanced engineering to the crank, and just about every moving part within. Cleaned the tank with phosphoric acid, the works. Everything new.
Started around 3rd kick from scratch...beautiful. Sounded sweet as a nut. I took it for a gentle 5 miler to start with, no probs and over the next few weeks gradually increased the miles with no probs.
Then one evening I was 30 miles from home and noticed a cough..Did a quick check of the fuel cap for a blockage but it was nice and clear and headed straight home. Well, the last 10 miles were touch and go, it was awful, coughing and banging..AAAGHHH!!!.. Im sure you all know what I mean.
Anyway i went through the whole checking process as we do finally pointing the finger at the, yeah you guessed it.. the Magneto!.
There are quite a few reasons why an A series wont start but I think the Mags are terribly problematic.
Mine was rebuilt during the build but I took it off and got another "expert" to take a look. He spotted immediately a prob with the condenser, though apprently worn bearings can cause havoc with dwell angles and so forth I was told. Anyway I popped it back and the bike has run flawlessly ever since.
Of course that doesnt mean other things are necessarily ok. On the subject of dry plugs. If they are dry then that can point to all manner of... carb sealing/barrel/head/compression probs.
Owning an old bike is a tricky business. You have to get your head into all aspects of it and learn more than you ever thought possible cause there's always going to be something that will catch you out.
But I would certainly recommend a mag check. They are in my opinion the achilles heel of what is a great piece of old time machinery.