ive been riding since 7 years old. i have had this 2007 crf250r for about four months. not many mods except exhaust. i found a 2006 kx450f tht i am gonna trade this weekend. im a bit of a speed demon and looking to race some. at this point in time i ride lots of tight trails as well as open logging trails. crf250r has been great bike. but i wanna go faster. i weigh 200pds. nd im 5' 10".
i really like the way i can throw my crf around. is the 450 to bulky for my style of riding???
i will also be at a local racing track lots of weekends if this helps

The KX is a good track bike.  It has a ton of power and handles pretty well.  The only concern with an 06 KX450 is that it is a 4 speed.  The transmission does not work real well for off-road riding (there is not enough spread in the gears).  First gear is too tall for tight technical terrain, and 4th does not work well for the open stuff we have here out west.  Tight trails will force you to use the clutch too much and the bike will then overheat.  If you are keeping it on the track it will be great, but if you want to use it on “tight trails” it may not work out too well.

CoKTM

Edited by coktm, 04 July 2012 - 05:51 PM.

I think the kx will be too heavy and tiring to throw around on tight trails. I would stick with the 250 if this tight terrain is where you will primarily ride,

I would stick with the 250 as well, it seems to be more what you're looking for than the 450.

I traded my 450 for a 250 2stroke because of the same reason mentioned above. It was a 4spd and overheated, stalled in the worst spots, and felt like it weighed a ton when it came to throwing it around on the trails.

thanks guys the info helped alot. nd i did not trade it. i think im jus going to beef it up, maybe with a header and a hotcam, possibly a high comp piston

If you are looking for torque a big bore kit is the most bang for the buck.  I have a buddy that rides a YZ250f with a 290 kit and it makes a significant difference.

CoKTM