Ok, I've taken my time to search through the forums and I didn't exactly find what I was looking for. So I'm going to ask. Everywhere I look people keep commenting on how fast the 2003 yz450s are. Why are they so fast, are they really that fast, and how? I have a 2005 wr450 it has a bit of getup and go, but I would like to make it comparable to a 2003 since they are 'supposedly' the fastest of the 4-stroke yz's. Could anybody tell me the difference(s) between the 2003 and lets say 2005 yz 450? Thanks in advance.