How can you tell the diffrence between years on a yfz motor??

[yfzrider45]

I'm looking to buy from a friends friend, and they have a 2007 motor, but it looks exactly like my 2004......is there ANY diffrence whatsoever i should be looking for?? becasue i'm thinking the 2007 and the 2004 should be a little bit diffrent on the outside!?!?!:confused:

[Ride1Rob]

There all the same bikes. A few screws here moved, a few bolts there moved, other than that... You can look at the decomp plug area to see a difference between the two. The 04's/05's have 439cc cranks and the rest are 449cc. But you can't see those ;)

[yfzrider45]

alrite, he showed me the title of his frame and it matched so i'm all set! thanks man!!