Right on Yamaha's site it says the new bikes are legal in all 50 states. This doesnt mean that everyone gets a bike that blows. They had to develop a new exhaust system with a catalyst in it to be legal in Europe. The EU emissions regulations were tightened up for 04, and since it would pass smog in Cali and still make enough power to please the European market customers they sold it in the US as well. Why bother having to send two different bikes with different manuals and such when just one will work fine? They developed the bike to be a sweet performer right out of the box. If there is anything to gain, find out what someone like Graves or the factory riders bikes are like. The people with the dyno who make a living going faster than everyone else will know the best mods to do.