For YZF-R6R, YZF-R6SR, YZF-R6RC, YZF-R6SRC
Yamaha's YZF-R6 is a 600 cc sport bike, first introduced in 1999, updated in 2001, 2003, 2006 and revised in the years in between.

Liquid cooled, four stroke, transverse four cylinder, DOHC, 5 valves per cylinder.
4x 38mm Mikuni BDSR.
Monoshock: adjustable preload.

Liquid cooled, four stroke, single cylinder, SOHC, 5 valves per cylinder.
Monoshock, preload and rebound adjustable.

The YZ250 is a 2-stroke motocross race bike made by Yamaha. It was launched in the 1970s, and has been regularly updated since. It is slowly being phased out and replaced by its more powerful four stroke rival, the YZ450.

The YZ450F is a four stroke big bore racing motocross bike built by Yamaha. It is considered by most to be the starter of the four stroke dirt bike revolution. It is a replacement for the YZ250, which is slowly being phased out.