Hi I just bought a 2004 kx250f and the only way to start it is to pop start it and it will only run with the choke on can anyone tell me what might be roung with it

 

I have had the same problem with my 04 250f. From the sounds of it you have a few valves that are bent and are staying open. Causing not enough compression to kick start it. How many hours are on it?..

 

Just bought and 05 and was having similar problems as far as having to run it with the choke on. After doing some research I found that these bikes have fuel adjustment screws under the carb near the float area. In my case the screw was all the way screwed in, when after looking it up I found that from the factory there supposed to be 1 3/4 turns out. I would look into this before anything.

 

yeah for the idling our best shot is to make sure the screws are set for whatever setting you had them on...... try not to make them idle too much........but always let a bike warm up before taking it for a rip. In my opinion.........step 1: start the bike with choke pulled out, warm up period for about 8 minutes...NO THROTTLE step 2: push choke in and go for a little rip nothing crazy.....step 3: come to a stop and make sure choke is pushed in.....bike should idle now without even adjusting the choke.