Spider, pondering over the thought that common sense might yet prevail and the anti-carbon bills will be kicked into touch over the other side of the water, got his pen and paints out and added a sly dig of his own:
Oi Graham, YOU know why my Matchless suddenly kept coking up its spark plug - it was that nasty little black plastic float in the AMAL carb which had sprung a slow leak! The result was continuous slight flooding and too much petrol being delivered to the cylinder. The float has been replaced and the bike has since done several hundred miles with no further trouble. This is my camping bike so roll on the next BSA John Bull rally in Belgium!