I'm the prowd owner of a new YZ426 as of 1 week ago. An intersting point when deciding my choice of bike were the brochures issued by Yamaha on the YZ426 and WR400. Claimed power outputs were 58hp and 48hp respectively. It was those 10 hp that made me buy the 426 rather than the 400 although the latter is more suited to the offroad racing we do here in South Africa. Is the 426 really that much more powerful? I had never riden any of the 400's before making my choice so I dont really know how my new bike compares to the 400 models in terms of performance. Any comments? Incidently my last 2 bikes have been KTM 300s (1998 and 2000) but I know my 426 would whip both of these in terms of tractible power. I must say that having recently ridden my 426 and a friend of mines KTM 520exc (another great bike), I cant ever see myself going back to a 2 stroke.