i have never really checked the tappets but i will have a really good look at the service manual on the forum and do so. the spark plug is brand new and produces a nice consistent blue spark. I have also left the fuel tap on this morning and will check if the tank runs dry in the afternoon (just in case the carby is flooding and im not noticing it).

I will also pull the carby apart this afternoon and give it another cleanover with the carby cleaner. (i have this funny feeling that an air hole might still somehow be restricted that leads to the main jet).

Im guessing i should be able to unscrew the main jet from the carby body to visually inspect it? (it didnt budge last time). I will make sure also that i didnt accidentally enlarge it while cleaning it out (as i suspect i might have), this would cause an increase in fuel flow i guess?