2008 YZ450 Warm weather jetting

Has anyone had any trouble with stock jetting on the 08 in 70 degree plus temperatures? My 08 runs great below 70 degrees, with stock settings

-160 main

-45 pilot

-stock needle clip in #3 pos.

-fuel screw 1-3/4

-leak jet 55

However its starting to get warm and I'm noticing the bike is getting sluggish off the bottom, with some hesitation. I adjusted the fuel screw and that didn't seem to help much, then I raised the clip on the needle, also, not much help. I'm thing about dropping the pilot jet? any advice?

My 06 ran great with:

-165 main

-45 pilot

-honda needle #2 pos.

-fuel screw 1-3/4

-leak jet #55

Whats your elevation/Temp/humidity??

Not sure on elevation, I'm in southern minnesota, i'm guessing 200 to 300 ft? Temperature is 65 and above that I'm concerned with. humidity is 50%.

I ended up dropping my leak jet from #55 to #50, and that seems to have solved my problem. I now have the snappy response I had when temperatures were near the 50 degree mark. I elected not to change the pilot since the leak jet controls mainly "off idle" response. I'm not sure why my jetting is different as compared to 06-07 jetting, but seems to be running good now.

I have had good luck with a #40 Leak Jet in my 06.

And I would try a 165 main.... It is also the easiest to change with only removing the float bowl plug.

Yeah thats no kidding. Trying to yank that carb off and on is no fun. I'm racing this weekend, so we'll see how this setup works. thanks for the info

I have had good luck with a #40 Leak Jet in my 06.

And I would try a 165 main.... It is also the easiest to change with only removing the float bowl plug.

165 main is way to fat for a stock 08.

Interesting. What makes you say that? The only reason I'm asking, is because it seems like most like the 165s in the earlier model years. I think my stock 08 runs as good as its gonna with the stock pipe and jetting. But I also am wondering whether I need to rejet for the Two Bros pipe I have. It was a huge improvement, again with stock jetting.

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