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1999 King Quad 300 misfire

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I have a 1999 KQ300 thats been sitting for about 3+ years while I've been away at school. So in the last couple weeks I've been trying to get it running again for a local event called mudfest. I dropped in a new battery, pulled the carb out and cleaned it up a little, changed the fluids and put in a new plug. After all was said and done, the bike runs, but not quite at 100%. I had it going this whole weekend and it never completely quit on me, but it will not idle, and I cannot take the choke all the way off other wise it starts to misfire. I'm a fairly competent mechanic, but I'm not too familiar with this bike, so I was wondering if anyone knew of some if the more common issues with these bikes. I read through some of the other posts on this forum, and tried a few of the suggestions, but it still is running a little rough.

Oh, and for what its worth, when I first started to mess with the bike, I noticed there was some sort of fluid all over the head of the motor, it looked more like oil but Im not absolutely sure.

Thanks in advance :wink:

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Welcome to QUADCRAZY! You may need to take that carb apart and rebuild it. Might have some corrosion from sitting inside of it.

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So it will probably just be worth picking up a rebuild kit for the carb. On that note, I tried to pull the carb once before, but I could not figure out how to detach the throttle cable from the side of the carb, which is why I couldn't completely clean it out. Anyone have any insight into how to detach it? Its not like the typical slide out cable thats in a throttle body.

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I would think that the carb just needs to be cleaned better, you need to get the thing all the way off, and take it COMPLETELY apart, and clean EVERY hole, jet and passage. I would also look in the gas tank and make sure there isn't any debris in there either. Wouldn't hurt to make sure the petcock is clean too. One other thing I would do is check the valve lash. Now, concerning that throttle cable you are having trouble with. There should be a plasic cover on the side of the carb that covers the throttle linkage. If you take that cover off, you should be able to roll the lingage up to the point where you can slip the cable out of its hole. You should be able to see the throttle cable going into the carb just above the side cover. Good luck.

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do the stuff dirtdemon said. there is a cover on the right side of the carb you need to take it off, be-aware on the o-ring gasket. then you need to open the throttle by hand on the carb to take the throttle line out. you also need to remove the choke cable on the left side with a 11mm wrench, remeber were the fuel /vacuum hoses go. now you can start taking it out, this is the hard part since the carb is very tight in between the engine and air box. i recommend sliding the hose clamps off and taking the airbox hose out first. the hard part is putting is back in. once you clean the carb and all the jets, with a needle and a compressor is the best way. the idle screw for the king 300 is 2 5/8 turns out from all the way in. the hard part is putting is back in.

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Thanks for the replies guys, turns out it was the low speed jet was clogged, had a tiny speck of dirt in it. The passage was so small I couldn't even fit a sewing needle through it, but I took think piece of copper wire and fed it through. The bike is running like a champ now. Next project: Get the QR250 running :)

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