Thanks for the excellent link to the excellent information. It leaves me slightly confused though. According to the information on that page a TCI is most frequently used on less sophisticated engines than CDI are. So I suppose the YZF-R6 could be less sophisticated than the YZF-R6S, but I wouldn't think so. At least not noteably, it must be used for a specific reason that I don't know, like the fuel ratio is larger in the YZF-R6 than a CDI could comfortably handle or something. I guess it just struck me as strange because the YZF-R6 is clearly supposed to be "better" than the YZF-R6S.