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Hard start won't idle

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Hey guys been following you guys for a while. I got an issue with my 08 kx450f it's been getting harder and harder to start year after year. So a friend suggested to re set the valves. So I did. They were a bit tight so I shimmed them. Re set my timing. Counted my chain pins and all. Still a bastard to start. Checked my plug decent spark. Lots of compression will stop my boot right in its tracks if I'm not putting everything into it. Checked my auto decomp. It's working. Once I get it started after wearing myself out. It will run hot and only with the choke on. Take the choke off and it dies instantly. Checked my hot start and it idles up when I pull it while running. So I don't know, I got fresh gas in it. Maybe something with the slow jet in the carb? New air filter. I'm a mechanic so I'm not totally retarded. But don't know carbs very much. What I do know is it looks not very fun to pull out. If anyone has any pointers I would be very great full. Thanks guys 

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Buy a new (not 'cleaned') pilot (slow) jet. Once installed and the bike ridden for 20 minutes, check the fuel screw setting for a good, smooth idle. It should be about 1.75 turns from gently closed.

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Thanks man! Does a guy have to pull the carb out for that? Then I'd have to pull the whole ass end off I think? 

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Thanks man! Does a guy have to pull the carb out for that? Then I'd have to pull the whole ass end off I think? 

No you just take the engine mount off loosen the boot screws and turn it and it should slide out. It's tight but will do it.
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Hey guys, I pulled the bowl off took out my main, pilot and leak jet found the pilot jet looked like it had a slight blockage. Cleaned it up and blew them out with compressed air Put it back together same thing. U should  just replace the pilot jet? With the same size?

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On 2017-05-25 at 6:17 PM, kx450f06 said:


No you just take the engine mount off loosen the boot screws and turn it and it should slide out. It's tight but will do it.

Hey guys I took my carb off and sent it in for a cleaning but I took my valve cover off again to look at the timing. What do you guys think? I got 29 pins between the marks, and  the crank mark is lined up. But maybe both cam gears need to turn one pin to the left from the picture? To line up the marks with the head properly? 

IMG_4139.JPG

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Hey guys I took my carb off and sent it in for a cleaning but I took my valve cover off again to look at the timing. What do you guys think? I got 29 pins between the marks, and  the crank mark is lined up. But maybe both cam gears need to turn one pin to the left from the picture? To line up the marks with the head properly? IMG_4139.JPG.7b3b3537267c51927c572df364393787.JPG

 

Yes it looks like it needs to be to left. Level with the head. I always put a screw driver down on the piston to make sure it is at the top. I think the cams turn twice to every one stroke of the piston.

 

 

 

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1 hour ago, kx450f06 said:

Yes it looks like it needs to be to left. Level with the head. I always put a screw driver down on the piston to make sure it is at the top. I think the valves turn twice to every one stroke of the piston.

 

Ok ya she's at tdc checked with a screwdriver. If I get the exhaust line PERFECTLY lined up with the head. Count 29 pins I end up with this on the crank timing line. If I line that up perfect. My exhaust line might be a half degree out of line. Like shown in the picture earlier. Seems like if I could hold my cam gears perfect and move my crank gear one tooth I'd be dead on. 

IMG_4140.JPG

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