I currently own a 2003 CRF450. I love the bike but with 2 years of racing on it, things are going to start costing money. I work at a yamaha dealership and my boss is pressuring me to get a YZF. I have yet to ride one but am not tottally adverse to getting one. Especially at cost. Any inherant problems with the 450's and how is it in the tight slow trails?