Took the '06 KX250F out friday so i Just thought i would do a little review of it.
Ran the bike in a week ago, and it was nice, so different to that of a 2-stroke. Very punchy the way it hands out the power, and that was just breaking in the engine.
Starting wise even when hot the bike fired up within two kicks, 4-strokes arnt renowned to do this especially when hot so this is a definate plus. I found the best way is to have long slow kicks with the hotstart pulled in, however with a 2-stroke its more violent rapid kicks and she starts up. But even when the engines cold she still fires up within a few kicks.
The power on the bike is fantastic. She would pull, even in deep sand on a 180 degree corner with no trouble at all. 1st gear is pretty short however fairly powerful, 2nd was the most used in deep sandy corners, with 3rd and 4th being used on the longer straight's. I didnt even get up into 5th as 4th was plenty long enough of a powerband to keep the speed up. There was a fairly long uphill whoop section (sand) on a slight left hand turn with the longer style, more spread out whoops, the bike easily carried the front wheel over them dipping the back wheel in each in 3rd, I could enter the 180 degree corner before this section in 3rd and have enough power there to give it gas as if i was clutching it on a 2-stroke.
Handling wise again perfect. The bike would go where the front wheel would point. With multiple line choices forming throughout the day i could literally pick any line i wanted and know i could take it with speed and rely on the bike a little more to power its way through the deeper ruts. I hav'nt tried the '05 KXF so i cant compare it with the ALI frame etc but it must make a huge difference to the bikes stability.
The brakes on the bike were perfect aswell, Kawasaki have designed a slightly different unit like half wavy half stock and they seem pretty responsive, even in wet sand they held up really well.
I've heard "rumours" about the older generation KXF's having cam troubles etc and this may be a cause for concern on the '06 however i have yet to had any trouble with the bike. She's running perfect!
The only thing I've changed on the bike are the clutch springs. I've heard that the stock springs are actually meant for a 2-stroke motor and cant handle the power the 250F motor outputs so I changed the springs to Pro-circuit's stiffer springs around £45 or $80. I would recommend these as its all ok having loads of power but if it cant be transferred into acceleration then its useless, as the clutch plates will just keep slipping. I changed the plates after breaking in the motor and I've got to say there is quite a difference, it seems a little more responsive off the bottom and feels more stable power wise the way its handed out.
Im going to set the sag up a little harder as its pretty soft for me stock but obviosly this is a personal thing and each to their own.
Summing the bike up as a whole i love it! amazing handling, awesome power and perfect brakes. Could'nt ask for much more, If your thinking about buying a new 250f then i would highly recommend the bike, obviosly i hav'nt tried any of the other 250f's so i cant really compare but its going to be tough to beat