help jetting my 426

3 replies to this topic
  • viking_in_wa

Posted February 12, 2006 - 09:02 PM


please excuse me for asking this question, i know there is a forum for jetting only but i am looking for model specific answers and you guys seem to have a lot of good answers. i have an 02 426 with what i assume stock jetting, i came to that only because until now it still has stock pipe. I am going to be installing a big gun system soon and would like some input on the correct jetting to use for this application, if anybody is running a big gun and what works best.

  • kizzle426

Posted February 12, 2006 - 10:50 PM


If you're making it breathe better, you'll have to richen it up a bit. I live in Texas where it's warm and dry. When I switch pipes (I have 2) I just make use of my Zip-Ty externally adjustable fuel screw. I start it, see if it pops or bogs, and adjust accordingly. Easy as pie. It may be that simple for you.

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  • 642MX

Posted February 13, 2006 - 11:15 AM


Kizzle is right, get an extended fuel screw for quick adjustments. When I put an aftermarket exhaust on mine I had to change the main jet to a 165 also. (Stock is 162)

  • bhollis426

Posted February 13, 2006 - 11:20 AM


I'm thinking mine has a kit b/c i'm running 52/178 and it's running perfect.

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