I don't know the gearing for the 450f but I know the gearing for the yfz is gear low. it tops out pretty fast compared to or quads. I know my yfz kills my friends raptor but I will top and he will catch up to me and start to pass me. I'm sure i could just regear it and beat him. Theres is plenty of power but the not enough gearing.
I personly think the yfz should be a 6 speed.
'09 KTM 505sx black
'06 YFZ white
Herrmann/elka, LSR, ITP, TAG, Hiper, Ac, Blingstar..........
'04 yfz blue
ITP, pro-circuit, gibson, gyt-r, LSR, Pro-tapers
2001 400ex #40
Axis, Lonestar, Herrmann, Gibson, Quadtech, JE, Hotcam, ITP, Ronnies, KandK, Roll design
Ronnie's Mail Order
www.ronnies.com
ATV fury3 -FST-..walsh..
ATV fury2-Sick0 number 40