From where ?

9 replies to this topic
  • ThumperWR450F

Posted March 24, 2003 - 11:46 AM


ok to adjust the pilot screw is it 1 3/4 turns out from the stock position or do i put it all the way in and back it out 1 3/4 turns?

  • Wicked_Crash

Posted March 24, 2003 - 11:51 AM


It is adjusted out from the fully seated position.

  • ThumperWR450F

Posted March 24, 2003 - 01:31 PM


ok so is stock fully seated ? :)

  • Wicked_Crash

Posted March 24, 2003 - 01:51 PM


No. When fully seated, it would be very unlikely that the bike would even run because it essentially closes of that jet. To adjust it screw it in to fully seated and then turn it out to your adjustment (1 3/4 turns).

  • ThumperWR450F

Posted March 27, 2003 - 12:48 PM


i screwed it in till it was fully seated than backed it out 1 3/4 turns and now it runs like crap. i'm gonna wait till my zipty screw comes in this way i don't have to keep unhooking the carb and tilting it out.

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  • Wicked_Crash

Posted March 27, 2003 - 01:06 PM


Not all are going to be adjusted to 1 and 3/4 turns out. To adjust it, after you let off the throttle:

if the idle hangs high then drops to normal, you are too lean on the fuel screw - screw it out a little to richen it up until the it idles normally without hanging above idle or dropping below normal idle

if the idle drops below normal then rises to normal, you are too rich - screw it in a little to lean it out until it idles normally without dropping below normal or hanging above normal idle

This is one of those things you just have to play with for a little while to get the correct adjustment. The zip ty screw should make it a lot easier to adjust. Do you know how many turns out it was before you adjusted it to 1 3/4? When you say it is running like crap now, what are the symptoms? Let us know so that maybe we can help you out. Let us know what your MJ,PJ,PAJ,needle and position and are you running with stock exhaust, airbox lid removed, elevation etc.

  • KiwiThumper

Posted March 27, 2003 - 01:29 PM


Is the Fuel Screw a Fuel jet or Air jet?
I thought it was an air jet, which would mean it would lean out as you screw it out
I could of course be wrong :)

  • Wicked_Crash

Posted March 27, 2003 - 01:35 PM


The one we are reffering to is the Pilot Screw on the bottom of the carb. What you are thinking of Kiwi is the Pilot Air Screw that replaces the stock Pilot Air Jet at the back (air box side) of the carb and you are right about screwing the PAS out would lean it out, but that is a different subject, for now at least. :)

  • ThumperWR450F

Posted March 27, 2003 - 01:50 PM


I have a 165 mj and a 48 pj . i didn't change anything else. snorkel and exhaust baffle removed. i am at sea level.

  • FNG241_WR450F

Posted March 28, 2003 - 04:36 AM


Check out the March addition of Motorcross Mag. It has about a 5 page article that tells you exactly how to adjust the screw. I had the same questions and the article helped ALOT. For starters, It tells you to run if for a bit never knew you needed to turn up the idle adjuster while you adjust the fuel screw. Recommends about 1800 rpm. It's a really helpful article. You can go to and order it. Good Luck.


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