Try our new info resource - "Aladdin's Cave" (Main menu)Just added a separate link to Ash's Dropbox thread (shortcut)
I could be wrong but I think the ES is just the new version of the EA (someone will tell me if i'm wrong i'm sure !!!). I was just making sure you were not using plugs with R in the title which means resisted, with resisted plug caps as that combination gives the symptoms you are describing with the fluctuating revs. I know this as I fitted the resisted plugs in error one time and had all sorts of problems !!!. As Roy said earlier, whip the plugs out after a run to get a general idea of if she is running lean or rich, my guess would be lean which is no good at all and running long term like this can cause serious damage to the engine(see my engine rebuild thread ).