KX85 not getting fuel help requested

My son has a 07 KX85 that is not getting fuel to the cylinder.  I have removed the carb about four times and see no problem, it all looks great.  I can remove the spark plug and drop a dab of fuel in and it fires right off and runs like the road runner once cranked.  If you lay the bike down on its side until fuel comes from the overflow lines, it will then pickup fuel and crank.  Once the bike cranks once it will continue cranking on first try the rest of the day, it's just the initial start-up.  Any help would be much appreciate as I've searched the world over trying to figure this out.. 


thanks in advance

Your post makes little sense. What do you mean by 'cranking'?


Do you mean, the bike will not start when kicking unless you prime the engine by placing a doloop of fuel in the cylinder. Then as long as the engine is hot, you can restart it by kicking?

Have you checked the reeds? Done a leakdown test?

Thank you, William for your response.  Yes, if I pour some fuel into the spark plug hole, it will fire right up and re-start the rest of the day without issue!!  I do have a faulty reed valve and actually received a new one in the mail today. 

Also, I do not know how to do a "leak down test"  :(

Well, you problerm is not jetting. It may well be the reed, it could be a bad crank seal or case issue. A leak down test is where the engine issealed off and pressurized and you look for a drop in pressure and then the source of the leak. It requires specialized tools and a compressed air source.


The fact that your bike runs once heated up tells me that what ever is preventing the engine from creating enough suction when cold resolves itself when hot (parts expand).


You may want to take the bike to a reputable shop to determine the problem if the reeds do not solve it,

Thank you William for your help  :)

Sound like a sticky needle and float to me, if leaning the bike over gives it enough fuel to start.  Could also be a idle circuit problem as well. Have you had the carb apart yet? And is the air screw set properly? My first step would be to clean and inspect the carb, having a good look at the needle and float, as well as checking the float height.

I installed a V-Force III reed valve last night and it still refused to start with kicking it alone.  Added fuel through the plug hole and bam!  This morning I went and tried to start it again and it started up first kick.  I guess tonight I'll try it again and hope it starts again, if so I'll called it "fixed".



Hasn't been figured out yet.  The reeds didn't cure the thing lol

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