Carl, you’re getting both cylinders to run so it’s got to be something that’s common to both.
You’ve eliminated, Magneto and contaminated fuel. Cam timing you haven’t moved so no reason for it to be an issue. I’m guessing if you have points cover with a kill wire you have already disconnected it and tested to see if it’s the cause, so that’s out. Plugs and HT leads are individual and you'ed have to be pretty sad case to have both sets of new ones fail straight up.
Only 2 things left on the list really; contact points circuit continuity or some kind of fuel starvation that is somehow affected both carbies i.e. a jetting issue (not likely if it was running fine 12 months ago & not been played with) or there is still some residual gumming hidden in one of the passages, possibly acting like a little flap on a check valve.
You’ve eliminated, Magneto and contaminated fuel. Cam timing you haven’t moved so no reason for it to be an issue. I’m guessing if you have points cover with a kill wire you have already disconnected it and tested to see if it’s the cause, so that’s out. Plugs and HT leads are individual and you'ed have to be pretty sad case to have both sets of new ones fail straight up.
Only 2 things left on the list really; contact points circuit continuity or some kind of fuel starvation that is somehow affected both carbies i.e. a jetting issue (not likely if it was running fine 12 months ago & not been played with) or there is still some residual gumming hidden in one of the passages, possibly acting like a little flap on a check valve.