I am almost embarrassed to post this but I am a but stuck. When I was running in the A10 GF I had no problems but now I am opening her up I have found that the engine starts to stutter. It revives if I close the throttle rarely cutting out. At first I thought is was lack of fuel but I have opened up both taps and the problem remains. Then as it occasionally backfires I retarded the ignition by a few degrees. Lastly I thought it was an electrical fault and in fact I blew a fuse due to fault on the horn/dip switch. After rectification it still stutters.
The 1961 GF has electronic ignition, and a new Amal carb. The charging system is working well and the battery full. I have carried out a plug chop stopping the engine when the stutter occurred and have included a photograph. I think the engine is a little rich as it starts up without choke or tickling the carb.
Where do I look next?
John