Need help deciding on a 2009 YZF 450

[twelve02]

I'm looking at getting a left over 2009 YZF 450 or 2009 KX450F. I can get the YZ for a really good price but have been doing a lot of research about all the 2009's and currently ride a KX250F and YZ250 for moto mostly. I read that the YZF 450 is a pretty good all around bike but that it's slow with the stock exhaust. I've also read that with an aftermarket pipe, the engine really comes to life, is this the case?

If this is true, what pipe have you guys and gals been getting the best performance out of, DR. D, FMF, other?

Also, does anyone use a DR. D radiator lowering kit or offset triple clamps to help with turning?

I like Yamahas and have had a few, they are durable as all hell and are for the most part good bikes, though the best bike I've ever had is my KX250f. That bike is awesome.

Thanks.

[monkeymotocross]

i had a 2008 rmz450 with a procircuit ti4-r and a bunch of other parts, just got a 2009 yz450 its not as fast, put a yoshimura exhaust on it and it helped alot, fuel injection is over rated this bike runs great. its just all round a great bike that doesnt do anything weird

[YamaLink]

I like the YZ450F better as an all around bike than the 09 KX450F we have. Both are very good but different in their feel and power application. Many do stick a Dr. D or similar pipe on the Yamaha.

In the hills I cannot ride the Kawi as well as the Yamaha in any form, stock or modded. But in the desert the Kawi is a better bike for me and my ability.

Based on feel and price and maybe even race contingency is how I'd select.