I'm looking to get a different bike this spring. Currently have an XR400 that I do like a lot but when I think about all the upgrades I'd like to do to it and how much it would cost,,, I just don't see the point. It will still be an XR400 (that's not a bad thing mind you) and I figured I could use that money plus a little and hopefully get something with a lot more modern suspension, way stronger motor and best of all, e-start! I'll never sell the XR, it will be my back up bike and I've had too much fun on it to let it go, plus it's plated. I'd like an 07 or newer WR450 but the used price is still very high. Is the major diff. between those and the older ones just the aluminum frame? I'm just looking for some real world feedback on the 2 generations. Besides the frame material, what would the advantage be to hold out for an 07 or newer? Were there any major changes made between 05 and 06 on the previous generation WR?