KX250 Idle

[rooster300ex]

My bike use to idle great. I wouldn't let it idle for long just long enough to get on the bike or going on a downhill and I needed to pull in the clutch. My question is what causes a 2 stroke to not idle like it use too? Could the idle screw have vibrated alil and just needs the idle turned up or what?

[crlt250r]

Idle screw, idle mixture screw, spark plug, crappy gas gumming the pilot, ambient temperature, humidity.... Fix em all. Especially the humidity, its really bad right now.. LOL

[rooster300ex]

I wish I could fix the humidity lol. The bike will idle alil and eventually wanna die. I'm just gonna try turning the idle up, and go from there.

[KXRida]

Rule of thumb is no less then 1 1/4 turn on the idle screw but no more than 2 1/2 or you need to make a jet adjustment. Made adjustments 1/4 at a time until you find the sweet spot.

[rooster300ex]

Originally posted by KXRida
Rule of thumb is no less then 1 1/4 turn on the idle screw but no more than 2 1/2 or you need to make a jet adjustment. Made adjustments 1/4 at a time until you find the sweet spot.

so ur sayin i need to adjust the airscrew/pilot circuit or whatever just cuz it doesnt idle perfect? it use to idle fine no changes have been done to this bike

[KXRida]

You should have an idle screw. It'll be a small screw with a spring

[rooster300ex]

Originally posted by KXRida
You should have an idle screw. It'll be a small screw with a spring

K got it. I figured that was the idle screw, but I didnt wanna go turning on the wrong one and get it out of wack. Also when I bought the bike it was the end of winter so the temps were quite a bit lower then now, and the hotter it has gotten the idle has gotten lower. Could that have to do anything with it. Does the air screw need alil adjusting or just stick with the idle screw for now??

[crlt250r]

You'll definitely need to adjust the air screw for temperature changes, and in extreme cases, rejetting. Cold air is more dense than hot air. When the carb works right in the winter, without changing settings or jetting, it will run rich in the summer. You can try to compensate with adjustment on the air screw, but may have to bump the pilot up. Also, try moving the clip one notch down on the needle, that will help with your mid to high rev.

[rooster300ex]

Originally posted by crlt250r
You'll definitely need to adjust the air screw for temperature changes, and in extreme cases, rejetting. Cold air is more dense than hot air. When the carb works right in the winter, without changing settings or jetting, it will run rich in the summer. You can try to compensate with adjustment on the air screw, but may have to bump the pilot up. Also, try moving the clip one notch down on the needle, that will help with your mid to high rev.

Thanks guy. I'll see what I can do, and if it doesn't work ill put it back how it was.

[rooster300ex]

Originally posted by crlt250r
You'll definitely need to adjust the air screw for temperature changes, and in extreme cases, rejetting. Cold air is more dense than hot air. When the carb works right in the winter, without changing settings or jetting, it will run rich in the summer. You can try to compensate with adjustment on the air screw, but may have to bump the pilot up. Also, try moving the clip one notch down on the needle, that will help with your mid to high rev.

I'm not use to 2 stroke carbs, but I know where the screw is. Its alil below the idle screw. Its a lil brass looking screw right? How many turns should I go? Turn it IN a 1/4 or turn it OUT a 1/4?. If i'm wrong on anything let me know. thx.

[chucked]

Considering its warmer now, the air is less dense, the bike is probably running rich, go out a 1/4 turn on the air screw. its on the side of the carb, on the same side as the choke between the slide and the airbox.

[crlt250r]

Rule I've always stuck with. Less than 1 1/4 turns out, or more than 3 1/2 on the air screw, rejet. Also, the air screw could be air, or fuel. Depends on its location in reference to the slide. Filter side of the slide adjusts air, engine side of the slide adjusts fuel, both are idle mixture. Really depends on the carb you have. Get the idle right, then do a plug chop to ensure the jetting is right.

[rooster300ex]

alright guys I finally got to mess with the bike. I got the bike warm,and adjusted the idle. I had to turn it alot and it didnt really wanna idle,so i turned it back quite a bit and messed with the air screw 1/4 or so at a time,and got it to idle great,but as soon as i stopped for a sec it was better,but still wanted to die. I think the carb needs cleaned,cuz the float hose vent sometimes drips gummie stuff out it while it sits

[KXRida]

Originally posted by rooster300ex
alright guys I finally got to mess with the bike. I got the bike warm,and adjusted the idle. I had to turn it alot and it didnt really wanna idle,so i turned it back quite a bit and messed with the air screw 1/4 or so at a time,and got it to idle great,but as soon as i stopped for a sec it was better,but still wanted to die. I think the carb needs cleaned,cuz the float hose vent sometimes drips gummie stuff out it while it sits

sounds like you may have found your problem. I'd be willing to bet you have some gummy jets as well.

[rooster300ex]

Originally posted by KXRida
sounds like you may have found your problem. I'd be willing to bet you have some gummy jets as well.

Alright guys. I pulled the carb, and it wasn't bad but needed cleaning jets didnt look bad but still cleaned with carb cleaner and alil compressed air. Cleaned air filter put the carb back on carefully. Also some fresh 91 with 32:1 klotz techniplate. Fired right up. Tuned the air screw till it idled with the air screw and turned the idle screw up a bit, and man this thing is getting it when u give it the bad **** lol. Thanks for everybodys help. Thats Y I love this site.

[KXRida]

Glad you got it worked out.