Fuel screw keep vibrating closed

Anyone ever have issues with there aftermarket fuel screw vibrating closed or near closed? Mine keeps doing this and it's getting kind of annoying. Its on my 05 yz. It has all its parts (in the correct order) I did try to slightly lengthen the spring, but still does it. I'm not sure what brand screw it is, it has a second o ring that seals around where it passes through the float bowl. Is this just a case where I replace the fuel screw or can I fix this?

Is the spring the original, or the one that came with the screw? I find that the OEM spring works best.

I was thinking of buying one of these SRP fuel screws to complete the rebuild of my carb and am wondering if I should leave it stock due to all of the "My Aftermarket fuel screw fell out stories"

If I leave my bike completely stock will I need to tinker with the fuel screw? I recorded the setting upon disassembly and it did start very easy when I bought the bike.

I am gonna go ahead and snag an aluminum hot start nut for sure.

Gray, I'm not sure it came with the bike. I'll order one and see what happens. Is there in your opinion one fuel screw that works better than another? Not that its the screw that's giving me trouble, just curious.

If you can stay away from the aluminum ones.

Brass is the way to go, just like the stock one. I had a brass one that had a nice little "t" fitting on the end.I Forget what brand though. Also I have notived the tips on some of the aftermarket ones are shaped a little different than stock.

If you can stay away from the aluminum ones.

Brass is the way to go, just like the stock one. I had a brass one that had a nice little "t" fitting on the end.I Forget what brand though. Also I have notived the tips on some of the aftermarket ones are shaped a little different than stock.

No argument there. I have had good luck with the Zip-Ty screws, but I always chuck their springs in the hardware drawer and use the OEM one.
No argument there. I have had good luck with the Zip-Ty screws, but I always chuck their springs in the hardware drawer and use the OEM one.
Have you ever actually looked at the tips and compared some aftermarket ones to stock ones? Not good.
Have you ever actually looked at the tips and compared some aftermarket ones to stock ones? Not good.
Some of them aren't even close.
Some of them aren't even close.
Amazing thing..makes it kinda hard to tune proper.

I had mine close (not open) years ago but the brass + oem spring combo has been flawless since.

I had the same problem and went with a R&D Flex-Jet set up. It adjusts beautifully and NEVER moves. Good Luck.

I just got a new oem spring, Ill try it out this weekend.

I lost one of the aftermarket screws on an '04. I took the carb off, and very carefully drilled a hole in the float bowl body adjacent to where the screw passes through the bowl and inserted a very small "hitch pin clip" in just the right place so if I got a little sloppy and loose with the fuel screw, there was no way it would come out without popping the clip out of the bowl first. Never lost another fuel screw on the '04, or my subsequent '06 either....The ultimate solution, of course, was to pick up a 2010 with fuel injection....never had an issue with the fuel screw at all after that....:smirk:

I had the same problem and went with a R&D Flex-Jet set up. It adjusts beautifully and NEVER moves. Good Luck.

I totally agree, I have a R&D Flex-Jet on of both of my bikes and they are great. They are made of brass and not only do they stay in position, but they make it much easier to tune your carb.

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