Other applications ranged from the Supersport YZF-R6 and YZF-R1 models using electronic fuel injection with YCCT and YCCI to the less extreme but still powerful Yamaha FZ6 (4 valve per cylinder) and FZ1 Fazer line which had a simpler fuel injection designs but was essentially the same basic engine design. The most significant changes made were the 4-valve per cylinder configuration and the crossplane crankshaft found on the YZF-R1 2009, along with the change of cylinder sleeves to steel for high precision and high temperature durability. Throughout its long period of production, the Genesis range has successfully provided performance and reliability.