Just to bring an update. Yesterday she would not start at all. Nothing. If I squirted some easy start into the carb she would run on that, but wouldn't draw, or ignite the petrol. Pump was fine, and there must have been a spark to get the easystart burning.
As if by magic a carb reconditioning set arrived in the post and I took the carb of and cleaned it. I replaced as many seals and o rings as possible.
Still nothing, by which point my battery had run out of juice.
I charged the battery last night and she started easily this morning!!! I also double cleaned the idle circuit just before this and had actually forgotten to put the idle adjust screw back in (this was at 0700 this morning which explains a lot). I have nit taken her for a spin yet, due to inclement weather, but will report back after that.
I think a new battery and a new coil will be bought just in case its a battery or coil issue. I have read duff coils give hard starting and erratic running when hot, which sort of matches my symptoms a degree.