Sorry to start another post on jetting..... :)

But I have not read anything about idle speed in the jetting posts. Idle speed/RPM's is a vital piece of information, because, an idle set beyond the factory specification of 1650 to 1750 rpm's will not bog, no matter how badly out of tune the AP or any of the jet's are! In other words, a poorly adjusted carb with a terrible bog off idle, can be concealed with a high idle!

My 05 WR450 is jetted currently with "JD RED 1st clip" a "#40 Leak Jet" a "170 main jet" and has the "Boysen Quick Shot" installed. No matter how I set the air screw, the off idle BOG is present if the idle is adjusted using a tach to the factory specs of 1650 to 1750! When the idle is adjusted beyond 2000 RPM's the bog is eliminated.

Heck, maybe there is not a WR450 on the planet that can be set to factory idle specs without a bog! If this is the case, then I would like to know how to get close to factory numbers with the BOG eliminated. And, the only way to know, is to start posting idle speed/RPM's.

To sum this up, I would recommend the idle spec be noted in off idle BOG jetting posts. Otherwise, the information is not complete.


Florida, currently 88 degrees with high humidity, and small chance multiple hurricanes! :)

You have your needle set on the 1st groove, i.e. at the top? That would be INSANELY lean. Drop it down to at least #3 and see what happens. I run my idle in the mid to high 1800's with a JD Red #5 and the bike seems to like that quite a bit...SC

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