Hey everyone, I'm new here, just wanted to do some research before buying a bike. Here's the story. My cousin has an '03 YZ450F that he got from a buddy. It has a bunch of ad ons, exhaust, bigger rad etc. and a new engine because the guy somehow sucked a bunch of water in and blew the thing up. Anyways he put a whole new engine in before my cousin bought it. Well my cousin doesn't ride it and said he'd give me a good deal on it. Just wondering if I should or if its worth it to get an '06 or newer? Only planning on a day a week at the track or some trail riding. Is there that much difference between the new and old frames? I'm a novice rider so I don't know if I'd even notice a big difference. I've heard some guys say the 4 speed works better for trail riding? Any input would be appreciated, thanks.