2 replies to this topic
  • Rocky

Posted December 08, 2001 - 01:55 PM


I have posted my jetting dilemmas over the past couple of weeks.

Current situation: 1999 WR 400

Main jet: 172 (Have tried 165-175)
Pilot: 45 (have tried 48)
Fuel Screw: 1 1/2 turns out (no effect what so ever as to what setting)
Needle: OBDVR raised to 5th clip position (tried 3rd, 4th, 5th)
Grey wire cut
Octopus removed, holes plugged MAJ #100
YZ timed
Air box lid removed
Stock exhaust with vortip insert


Regardless what jetting combo I am using:

Bike starts first kick
Idles perfect
Midrange sucks (burbling or popping sounds)
Top end sucks (burbling sound)

Also, at midrange, the bike sounds like it is whistling --- is this an air leak???

I need help with jetting.


[ December 08, 2001: Message edited by: Rocky ]

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  • yzernie

Posted December 08, 2001 - 02:23 PM



Sounds like you are running too rich. I guess that Tempe is no higher than 1000' elevation?? Pump gas or race fuel?? Try these setting as a baseline and you can fine tune from there:

42 pilot
needle stock clip or one clip leaner
165 main
fuel screw 1 turn out

This should get you in the ball park. If the fuel screw has no effect when turning it in or out you are too rich on the pilot.

Make sure your air filter is clean and not over oiled, your gas is fresh and you keep an open mind while playing with the jetting.


  • Paul_Thistle

Posted December 08, 2001 - 02:59 PM


Rocky, Did the bike ever run correctly with the cams retimed?PT


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