I'm about 5'11" and around 250-260 lbs and am wondering on which bike to get. The YZ426 or the YZ250F. I've heard stories of people being able to go faster on a 250F. I'm almost a novice, a few more weeeks of practice and I should be a starting out novice. With the 250F I'm afraid of the my weight/bike power ratio. Lookin' for some oppinions here....thanx.