Midlifecrisis: The 08-09 YZ450F stock motor and exhaust needs no de-tuning for off road riding. They did it for you from the factory. Excellent machine. 11 lbs heavier than a YZ250 two stroke. Of course the WR offers the button, 18 inch wheel, trail suspension etc but if on a budget these "slow" MXers are good for off road too. Its actually about 20lbs heavier than yz250. Agreed though on the motor, it is a great motor for offroad riding. Its still one of the best track converted for trails bike I have ever owned.