From stock to Slip On (Main Jet?)

3 replies to this topic
  • markturbo

Posted July 16, 2007 - 08:46 AM


How many sizes up on the main jet do you go from a stock pipe to a slip on? I have all the free mods done to my 2006 450 and am currently running a 168 main. But today I just oredered an "FMF Speed" slip on and I don't know what main to run.

  • StreetbikePimp

Posted July 16, 2007 - 09:49 AM


Call FMF specifically and ask them. They will tell you what the proper jetting specs are for that pipe.

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  • Just_a_trail_rider

Posted July 16, 2007 - 12:01 PM


I have an FMF Factory 4. I initially ran a 170 main, but like it better with a 168. it was just a little bit sharper on the bottom end and didn't seem quite as fat.

I also have the red needle at position #4. I normally ride in Lucerne , Red Mountain or Cal City.

Your terrain, elevation and conditions may require something different.

  • KennyMc

Posted July 16, 2007 - 12:30 PM


I have all of the mods done as well as the FMF Powercore slip-on. I went with the JD Jetting recommendation of the 168 main, 48 pilot and the red needle on the 4th position. I ride anywhere from Johnson Valley to LPNF and the bike has performed fantastic:ride:


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