aforth

I have been turning some crew on the carb that I have been told controls the air/fuel mix..? But I have now read somewhere that there is also a screw for the fuel idle? What am I looking for in the fuel tank bud? Should there be a hole in the actual fuel cap? Thanks A

I have a 2011 lambretta evolution with a lexmoto 125 4 stroke engine Father replaced air filter before it came down to me with a orange triangle looking thing No every now and then when I am caning it - it can splutter and stall - I wait 10 seconds - and it starts right back up again! Is this something to do with the carb/ air / fuel? Will a tinker with the fuel nut help at all? is it too tight or loose do we think? Someone said I need the jets altering to account for the new filter but want to sort it for short term before this gets done Thanks in advance Aaron