1998 KX250 bogging in at high RPM

[Jopiz]

This goes a little offtopic, but could it be saved to Howto's ? Very many issues are because inproper fuel level.

[hughes]

This goes a little offtopic, but could it be saved to Howto's ? Very many issues are because inproper fuel level.

I'm working on getting it turned into a pdf file for easy viewing. We've talked alittle about redoning the "How To section".

[mr.5thou sand]

do you have clean air filter/what is your main jet. spark plug. crank seals. did it start doing it out of no were

[bigspeights]

I am going to have another go today at getting the bike going. does anyone know what the float height is for a 1998 kx250. I was told 16 mm by the bike shop but they have been wrong before.
 

[KXcam22]

The seam in the plastic of the float should be parallel to the carb body at the exact instant that fuel flow is stopped, generally 16-18 mm. Cam.

[bigspeights]

I have set my float right agian and still same problem. I have also cheaked the bore and there is no scratchs or any marks, I have cheaked the power valves and they seem to be working fine but I have not cheaked them while the bike is running. I have cheaked the reeds and they seem fine. I have put a new plug in the bike (NGK BR8ES) had a quick ride and the plug was light gray. after that I raised the float. I have not been able to ride the bike yet but I know that this will not fix it. What is wrong with my bike. I cant work it out. I even sprayed CRC on all the electric leads and gave them a clean. What else could it be and could it still be the carb even though I have cleaned it out about 3 times and have changed the float about 15 times and tested each time with no luck. I still find that the bike runs bettter with the choke on after I have been riding for about 10 mins. I getting sick of riding a bike that goes like crap. when I am riding on an open bit of track or I just want to open it up the bike justs has no power and boggs down.

[Jopiz]

I wouldnt do any adjustments to the float level once its paraller. Could your jetting be too rich or too lean?

Heres what PC recommends: 

KX250            
158 main 
45 pilot
NOZG  needle 3rd notch
Power jet 55
Air screw 1 1/2 turns out

[bigspeights]

thanks for all your help. The problem was low compretion, the rings were gone.

thanks again guys and have a good one