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KX idle speed with the choke??

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Ok so I finished putting my 2003 KX 250 back together and threw in the following jets

160 main

45pilot

#8 slide

I also have a 13oz flywheel weight with the stock pipe and PC spark arrestor.

Now I think I have it set so it can idle when warmed up and it seems to run fine...havn't taken it out for a true test yet though...when warm.

Yesterday after the bike cooled down and had been sitting I figured I would give it one more heat cycle real quick why I had the time.

Kickced it over with teh choke and it fired up but it seemed to idle really..higher then you would think it should. I got nervous about it and looked it over and did notice that I had a few loose reed cage bolts and two of them about ready to fall out so I killed it. Dont think it was sucking air or anything though.

Now I havn't had time yet to pull all the crap off to get to the bolts I need to tighten on the cage ......so my question is this:

Should a 2 stroke idle seemingly twice as fast as say a 4stroke would with the choke on? Also would an air leak at the reed cage cause this as well?

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Yes, those loose bolts caused an airleak which caused the high idle. Tighten them all down and it should be fine. Hopefully you didn't run it too long and roach the rings.

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Well I only started it and ran it for like 10 seconds before I noticed the loose bolts.

Yesterday I prolly ran it for 10 mins after having the bike tore down for 2 months.

Now I remember that I never really torqued the reed cage down....:p

The rings in it now are new though.

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Well I only started it and ran it for like 10 seconds before I noticed the loose bolts.

Yesterday I prolly ran it for 10 mins after having the bike tore down for 2 months.

Now I remember that I never really torqued the reed cage down....:p

The rings in it now are new though.

if the bolts were hand tight enough on the reed cage to draw air and fuel thru the carb, then you should be ok. besides, it sounds like it was sealed the day before, and might have loosend with the vibrations and only leaked some air for the 10 seconds you ran it today, i think theyre fine, if in doubt pulll the pipe and look

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Well im a little irritated now. I tightened the bolts started it up and it ran fine for a couple minutes then shut down. Figured I fould a plug with all the idling tests. Pulled out the plug and found peaces of what looked like a old rubber band type material plugging the plug! ***! :) I just went through the entier motor splitting the cases and everything! I never installed the piss you off rubber band in the top end!

So im hoping that its just a chunk of the reed cage gasket ....its just that this junk dosnt look like gasket material.......maybe I got a little to much case sealant in the crankcase? Do you guys think im hosed and have to tear down the motor again?

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Sounds like case sealant. Just run the bike bro as the rings sound okay. That stuff will burn up and be spit out the pipe.

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Im kinda leaning that way myself. Think I will go ahead an throw the plug back in and give her a shot:thumbsup:

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I have had an 01 KX 250 from brand new and it has always idled that way with the choke on. Usually, if I need the choke to get it started I turn it off as soon as it fires up.

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I have had an 01 KX 250 from brand new and it has always idled that way with the choke on. Usually, if I need the choke to get it started I turn it off as soon as it fires up.

Same here with my limited time on my 02, the idle circuit is really fast. I just feather the choke until it will idle without it.

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Usually, if I need the choke to get it started I turn it off as soon as it fires up.

me too

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These bikes really shouldn't need to idle. U should be turning the choke off immediately after it fires up and managing the throttle with ur hand. Its not bad for the bike to idle by itself but it does not have too. Just hold the throttle at 1/20th throttle if it doesn't idle.

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Same problem here that I was going to post. When I start mine with the choke on it Idles to the moon.

I was wondering if there is a way to adjust the choke or not?

I have had a few other branda and none idled that high at start up. I immediately turn it off but it just doesnt seem good for the cold motor to rage when first started,. Mine is a 2001 kx 250. I know my brother has a older cr 250 and there is the adjustment under the choke knob. Any help???

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