there's something not quite right there, the only real way your setup could run correctly with an 80 jet is if you had an airleak or if someone has removed the snorkel from the airbox- otherwise you would be well down on power -the ZX pipe in the graph below has identical jetting characteristics to the S6 Pro rep when fitted to a standard 50...
your probably right, but the evidence is the bike pulls to 90klms/h nicely, no spluttering, no hunting etc. burns very cleanly.... and the bike is a brand new bike (unmolested) only 900klms on the clock... The bike is completely standard other than the S6 pipe and a Polini hi speed variator with 3.5g weights... stock filter, stock air box with snorkel