I am planning on getting the 06 450R this summer. I was told that the 06 allready comes with a hrc power up kit. It is supposed to be the same as the 05 with the kit installed, but i dont know if that is true or not. I have also heard that it doesn't and if the kit and a slip on is installed it will put it up to 50hp. Which is true.

 

The 06 is highly updated, but it doesn't come with the HRC kit. You have to buy and install it yourself. I'm not sure about the stock or HRC hp ratings.