[Rapscallion St Croix]

I could give you proven facts regarding this subject, but instead I will give you a first hand anecdotal report. I have had my cart five years. I do not know what the previous owner did with respect to fuel, but I have only used Shell with no additional additives because that is what is available to me. My cart does not use a drop of oil. It starts easily every time. It runs strong and smooth always. Every time I check the spark plug it tells me that my engine is burning fuel efficiently. I conclude that both pieces of advice you received are wrong. You do not need additives but if used as directed, they will not harm your engine.