2004 KX250F Leak Jet?

Having problems with my bike. It runs when starts, although doesn't want to start without choke, hot or cold, and has a hesitation at very first twist of throttle.

Is this a leak jet problem or a Pilot problem?

couldn't be a pilot, as it is already a few sizes bigger.

did you have the slide out of the carb at any point?

Eddie, he has a 42 pilot, 178 main, stock leak jet. The slide has never been

out. Had a leak down test, compression test, and valves done about 8

rides ago. Also has a Big Gun slip on and run on regular pump gas at about

sea level. Also noticed that his fuel screw may be stuck. Anyway of free it

up. Bike is a little hard to start after it is warm and requires the choke. It

has a flat spot at a quick blip of the throttle. Any ideas for this kid?

if the fuel screw is actually stuck i would say the tip of the fuel screw is probably broke off in the carb.

Eddie, double check the fuel screw it is not stuck, just takes a very thin

screw driver to get in there. I have it set at 1 1/2 turns out. Any other

ideas? Also if your wondering who I am, Dirtbike Dudes dad. Reading every

thing I can on this site about pilot circuits. Just a little lost here. Thanks

for your time.


did this bike ever run correctly?

did you buy it new?

bought the used a couple of years ago its an 04. have some some issues

with it such as idling and hard starting when warm. I ve tried adjusting the fuel screw it is set at 3/4 turns out and cleand the air filter. this morning it would only sart with the choke out, even when its warm. but wouldnt idle.

now it wont start at all!!!!!!!!!!!!!!!!!!!!!! also being that the fuel screw is so hard to get to, I need to loosen the carb, and twist it sideways to adjust it.

you are 100% sure the slide plate is sqaure end down?

no, I am not 100% sure about the slide plate. But I never had the slide plate

out. but after letting it cool down a bit it fired right up with only the choke

on and poping quite abit. the bike ran fine last weekend but buy the end of

the day it was become harder to start and have a flat spot when you blipped

the throttle. all I have down during the week was put in a fresh air filter

and try adjusting the pilot screw. the owners manual calls it an air screw. so is it a air screw or a fuel pilot screw? long time 2 stroke owner and still

confused with 4 stroke carbs.

i would confirm the that the slide plate is square end down.

also look at the hot start cable.make its not bound up and that the plunger is stuck.

makes sure the pilot jet is clear and that the fuel isnt water contaminated.

you shoud also check the valve clearance.

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