Jetting question - need help.

4 replies to this topic
  • nothingleft

Posted December 27, 2005 - 01:24 PM


According to the chart listed below from Indy450. I should be jetting the bike for the 75-90 degree range for my area.

The 2006 WR450F stock has the following jets installed according to the manual:
165 main, 45 pilot, 65 starter, and 50 leak.

Does this mean all I have to change is the pilot and starter jets along with the JD Red #5?

Is it worht rejetting the bike based on such small changes?

re-jet the bike using INDY450's jetting chart:
Elevation 0 to 4,000. feet

30 to 45 degrees: 172 main, JD Blue #5, 48 Pilot, 2.0 turns, 75 starter jet, #0 leak jet
45 to 60 degrees: 170 main, JD Blue #4, 48 Pilot, 1.75 turns, 72 starter jet, #0 leak jet
60 to 75 degrees: 168 main, JD Blue #3 or JD Red #5, 48 Pilot, 1.5 turns, 70 starter jet, #40 leak jet
75 to 90 degrees: 165 main, JD Red #5, 48 Pilot, 1.25 turns, 68 starter jet, #50 leak jet
90 degrees plus: 160 main, JD Red #4, 45 Pilot, 2.0 turns, 65 starter jet, #60 leak jet

  • bg10459

Posted December 27, 2005 - 02:13 PM


Indy's chart is a very good baseline, but it was figured for his 03 with his mods, so it's not set in stone. I don't know what's different about the 06, but as you are pretty close to his chart, I would just see how it works. If you see any particular problems, address it at the time.
BTW, it's real easy to change the pilot jet if need be. I personally like to run a richer starter jet because it seems to help with cold starts, and my bike ran best with a 50 leak jet when the chart called for a 40. :applause:

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  • Indy_WR450

Posted December 27, 2005 - 02:31 PM


Good point my chart is a good base line for a modified 03 WR450.
However depending on how open your pipe and air box is will make subtle differences. Also the 05 and 06 have milder combustion chamber shape combined with lower compression. All these will make some variation from the chart. The real advantage is to use the chart as a guide for going on trips to different elevations or weather. I ride all over the US so I developed the chart so I could rejet at home instead of during the ride trip. :applause:

  • troys450

Posted December 28, 2005 - 11:51 PM


i put a 170 main,48 pilot,needle is stock,fuel screw bought at ms in riverside 1.75 ish turns out.starts easy,hot n cold,no popping on decel,no flat sea level to 4000ft.

  • snakesausage

Posted December 29, 2005 - 09:59 AM


I compiled a summary of all the 2005 WR450 jetting posts on the jetting sticky thread.


Hope this helps.


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