New (used) bike this summer.

Don't go with anything older than 2007, but don't get caught up in fuel injection yet, just get a bike that has low hours and wasn't raced. Also make sure the engine cases aren't scuffed up, that is a tell tell sign of how hard the bike has been ridden. As far as brands stick with kawi and Hondas. Those are the best.

Ive always heard that Yamaha had the most reliable engine in the 450's? or most forgiving maybe?

Literally, any newer bikes in the last five years will make about the same power. Some have problems, so you should look into the bikes individually. I'd look for an RMZ450. Picked mine up for $4500 with 6 hours on it. Guy didn't like it, so he sold it back. Got a good deal on that one.

The RMZs turn very well in corners and mines a 2012 and I have to say it's fantastic in my opinion, but then again, I'm sure I'd like any bike I ride.

If you're fussy with what the bike feels like, ride one.

You can't go wrong with any brand, and contradictory to what the guy said above, FI is much simpler and easier. Yes, there are more electronics, but it's so much better than fiddling with a carb if it's not jetted right.

Again, I'm sure any brand is alright. Yamaha, Honda, Kawi, KTM, Suzuki, any of them will last if you aren't really racing it on the rev limiter 24/7.

It's more of the condition of the bike than the brand. Post some up from your local CL and we can judge them if you'd like.

Thanks, I know there isnt a superior brand like some people say, if there was obviously thats what all the pros would ride. I have always been a Kawi guy, grew up on an 80, 250, 04 kx500 but actually prefered the xr600 over it at the time. Ive ridden all the 450's (not new ones though) except a ktm. And all feel about the same really to me. Same pull.

When you find one that says fresh top end, is that a bad thing? Would it mean that the bottom end might not be far behind in needing a rebuild?
I'll post back up likely when I am 100% in the market and ready with cash to buy for some comparisons.

For 4k, and if you're willing to maybe spend a bit more, you could find a mostly stock bike on CL. Find one that has low hours, ridden by an older guy, that actually takes time to write out the ad and describes it well.

The quality of the bike can usually be shown through the way the guy writes and describes it. If he takes time to write it, describes what's wrong with it, if anything, and the ad makes you feel depressed because you're buying a guy's favorite thing, then do it.

Couple things you might want to consider:

In the mountain west fuel injection can be very convenient. Not having to fiddle with jetting when making large changes in elevation (very possible when mountain trail riding) or when riding at cooler temps in the spring and fall.

From my experience a vet raced bike is usually a pretty good buy. Vets usually have more money to spend on upgrades, maintenance and aren't hard on things. I am usually the as concerned buying from some one that just play rides as much as a hard core racer.

You can easily pick up a 2008 Honda CRF 450 for less than $4,000. In 2008 the 450 Honda not only swept the reviews but in MXAs opinion would have won the '09 shoot out hands down. I went through this same thing a couple years ago and noticed that to get a better bike than the 08 I would have to spend at least $1000 to $1500 more. You can pay for ALOT of upgrades for $1000 - $1500.

I have ridden Yamahas, KTMs and now a Honda. One thing that I have really enjoyed is the limitless number of options to help improve the bike. I'm a taller guy (6'3") and the IMS low boy pegs are awesome to help open up the cockpit.

Good luck and if you have any additional questions I would love to help.

Thanks for the reply and yeah not having to mess with jetting would be great! I'll take the advice and look for a 08 crf. KX450 was EFI in 09 and RMZ in 09 I think too? So atleast I have some options.
kx went 5 speed in 06 though which is cool but Id have to give up FI.
Did any of them come with hour meters stock?

Correct both the KXF and RMZ had EFI in 2009. The CRF also had WFI in 2009, but didnt get as good of reviews. The transmissions on the older Kawis always got poor reviews and I cant remember when that started to change. To my knowledge none of them came stock with an hour meter.