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08 kx450f wont idle or start hot

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I recently bought a 08 kx450f. When I tested out the bike it started and idled fine, and seemed to run great. I took it for a good ride and noticed when I stopped it would die, then wouldnt start. It takes about 30 kicks to start, but if I wait for 5 minutes it starts up first kick and runs fine until I let the rpms get low.

I should note the hot start was stuck when i bought it, and I pulled it out, cleaned and replaced it. Now it doesnt seem to function properly (will open but wont close on its own) I dont know if this is an issue, or is something else going on? Any help appreciated, Im beginning to worry Ive been screwed.

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Exact same thing happened on the 2007 my buddy just got.  I actually went and looked at it for him before he bought it, started right up and idled decent but a little high.  He then took it out for the first time and then called me complaining that it was messed up and hard to start and would die at low rpms.  Anyway took out the pilot jet and you could barely see through it, put in a new one and problem solved.  Check/clean the pilot and see if that helps.  Is it back firing on deceleration?  If so you may want to also bump up to the next size pilot.

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js, It's too early to get worried about anything. Persist and fix that hot-start plunger and cable. Keep cleaning and lubing the cable and plunger, or replace if you cannot get it to work smoothly.   Hurricane is right, the pilot jets do easily get build up in them. Try a new one. It can make a big difference.

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Yup a new hot start is already on the way and it doesnt backfire at all just pops a few times. Going to check inside the carb today, hope thats my prob.

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If you are going to rip into the carb, then something else worth replacing is the slide vacuum plate seal. If worn or perished then it typically causes stalling issues, but I suppose it could also effect idling quality.  I got a new one for about $20 on ebay. Search for "keihin vacuum plate seal".

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