Fact or fiction fuel injection

I believe a properly adjusted carburetor is more fuel efficient than fuel injection. I have gotten on a TE610 27km/l with FCR, my friend with a 2009 Fi only managed 22. On a CRF 450 X I had 24 km/l with an FCR, any modern 450 with Fi will not get the same consumption. I also heard a KTM 950 is more fuel efficient than a 990 ? On the flip side I do know that the BMW F650 Dakar and X-Challenge is quite frugal. Your experience ?