Just curious how they compare, which is quicker, which has fastest top end, best one in your opinion.

why I ask is a bud rode my 07 said it felt a lot different than the 02 he had.

 

Yeah it felt different...a new bike always feels better than a tired old one!

I have an 00, and a friend's wife has an 07. I have ridden the 07 quite a bit, and I would say the suspension is improved over the old ones (but mine has Works Preformance shocks, and eats big desert whoops like no other machine on the planet!). I do think the engines are identical, but they geared the 07 a little higher...and of course it has reverse.

I wouldn't obsess about the "which is faster" kind of stuff. Anybody can make gearing changes on any chain drive and get more top end speed or low end power, whatever their personal desire happens to be...

 

My trail bike is a 2000 400EX and my wife has an '06 400EX.
Like reconranger said, they changed the tranny gearing a little in the newer models, they also changed the carb.
Hers definately rides smoother but I attribute a lot of that to mine having 8 year old shocks on the front. I put a 450R shock on the rear of mine.
Hers feels like it has more power, I piped hers differently than mine.