Pilot Screw

8 replies to this topic
  • Vet28

Posted May 21, 2004 - 01:35 AM


Has anyone had to adjust this? My '04 450F seems a little rich off the bottom. :thumbsup:

  • sirthumpalot

Posted May 21, 2004 - 03:02 AM


All the time! You need an extended fuel screw. There are several available, here is the ZipTy model:

ZipTy Fuel Screw

  • Vet28

Posted May 21, 2004 - 04:14 AM


you have to drop the float bowl every time? i thought the extended screw made it accessible externally somehow? thanks for the quick reply. oh ya...do little adjustments make a noticeable change?

  • sirthumpalot

Posted May 21, 2004 - 03:12 PM


No you don't drop the float bowl.

Yes the other screw sticks down far enough to adjust it with your gloves on.

Yes minor adjustments are noticeable.

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  • Vet28

Posted May 25, 2004 - 06:21 AM


Excuse the dumb questions, but I'm guessing more people ought to be asking about the fuel screw. Once I buy the aftermarket screw and I want to adjust it, where does it hang out of the carb? Does it stick through the bottom of the bowl, or do you take off that drain nut and adjust through there? The manual isn't clear.

Appreciate all the help.


  • Sean_McCutcheon

Posted May 25, 2004 - 09:12 AM


The extended fuel screw sticks out the bottom of the bowl, so you don't have to remove anything.

  • 4two6stroker

Posted May 25, 2004 - 09:17 AM


The screw from ZipTye is great and easy to see and adjust. The difference in elevation and temp changes I ride it helps get the carb just right.

  • sirthumpalot

Posted May 25, 2004 - 04:10 PM


Look under the carb and find the hole that you have to stick a screw driver into to adjust the stock fuel screw. The longer fuel screw is simply long enough to stick out far beyond this hole, and it has a knob on the end that makes it very easy to turn with your fingers. No carb disassembly is required. Just loosen the carb, rotate it sideways (for clearance), remove the stock screw and put in the new screw.

  • Vet28

Posted May 26, 2004 - 01:42 AM


thanks for that info. I will order the Zip Ty screw today. I didn't realize US bikes were jetted different than the 450's that go to all other countries. Canadian, European, Aus & New ealand all get 172 main and 45 pilot. US bikes get 165 main & 42 pilot. I guess my 2003 450 was headed to the US...I had the smaller jets.


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