WR 426 idle issues

5 replies to this topic
  • nordik

Posted January 29, 2011 - 03:49 PM


Hi All
I've got a WR 426 that sat for around a year. After resuming riding I was having some fuel leaking issues. At that point I installed a new needle and seat o-ring which seemed to fix this and at the same time installed an adjustable fuel level screw and jet kit.
If the idle is set below the "hanging point" at which the idle tends to run quite high it will periodically die while idling. I ride it as a dual sport so it is always at a stop light :thumbsup: My next action is to clean the carb again and install a new needle and seat, any other obvious things to check?
One other note is that it has an '03 YZ cam and no comp. release.
It always needs the cold-start lever pulled to start if its been sitting.



  • William1

Posted January 29, 2011 - 06:03 PM


TRy a new pilot jet.
You may also want to replace the needle jet emulsion tube, check it with a magnifying lens to confirm it is not ovaled at all.

  • nordik

Posted January 29, 2011 - 06:42 PM


THank you. The pilot, main, and needle are from the thumpertalk kit (I should remember I just copied what other WR426 YZ cammed CA riders were happy with) so I'll check the needle jet tube when I go in to replace the needle and seat. If the bike is running right will it idle indefinitely?

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  • 02WR426Cali

Posted January 29, 2011 - 09:25 PM


Yes it should idle with no problems if set up proper. Try turning the fuel screw out a little. What's it set at now?

  • byggd

Posted January 30, 2011 - 07:32 AM


installed an adjustable fuel level screw

I have the same bike with a 03 YZ ex. cam etc. The 02 doesn’t have a hot start lever, the hot start function is a knob right next to the choke knob on the carb. There is no fuel “level screw” so I’m going to assume you mean an idle mix screw. How many turns out is it set currently? As already stated, start by replacing the pilot jet. Yes the bike should idle indefinitely if tuned correctly.

  • 02WR426Cali

Posted January 30, 2011 - 09:31 AM


Byggd - he means the fuel mixture screw.


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