Got a pair of Webber IDF's fitted on my 1835cc engine, over the last few months I've done some tuning and changed oil pump system, the clutch and exhaust system.
Finally got engine re-fitted and took it for a test drive, started ok as I have an engine test stand so we did set things in motion on that. Well a couple of miles down the road when we slowed down and came to a stop the engine "on tick-over" went lumpy, it was fine previous to that. Accelerating from stand-still was okay apart from the tickover so made our way home and workout what the issue might be. A bit of info gathering and research and I came across this guy,   https://www.youtube.com/watch?v=fzf18S-HVOg&ab_channel=VicFerrari%E2%80%99sgarage 
the explanation and the way he described it made the sort-out seem really easy. found out cylinder number 1 was the issue, took the carb off and did what he described could be the problem, found a tiny bit of muck in the tick-over jet and did a clean through the system following his explanation. so far so good.
Thanks Vic Ferrari 

Cheers H

Tested again today

Sorted

H

I like my Solex P40's as all jets are easy to unbolt outside the carbs so cleaning and changing takes seconds