Had the same on my Ducati ST4S, parked under the eves of our Gite during a rain storm and no gutters in south of France, in the morning one cylinder coming in and out wouldn’t rev all the same symptoms you describe managed to chug over to Ducati Perpignan bought some WD40 and lifted the tank an sprayed everything I could see electrical etc in a cloud of steaming WD hit the starter smooth as you like and went like a dream, lots of water can sit in places, causing an intermittent fault electrics are gen on or off, after a lot of rain just blow WD over your motor it dispels damp, 👍 …… Pete🇫🇷
Had the same on my Ducati ST4S, parked under the eves of our Gite during a rain storm and no gutters in south of France, in the morning one cylinder coming in and out wouldn’t rev all the same symptoms you describe managed to chug over to Ducati Perpignan bought some WD40 and lifted the tank an sprayed everything I could see electrical etc in a cloud of steaming WD hit the starter smooth as you like and went like a dream, lots of water can sit in places, causing an intermittent fault electrics are gen on or off, after a lot of rain just blow WD over your motor it dispels damp, 👍 …… Pete🇫🇷
How did you sort it? What was the diagnosis?