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The Old Air/Fuel Tango

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This has probably been asked before, but I couldn't find specs on a search. I have a simple question, or at least it seems simple. After the third time with the carb off, I still don't have the jetting where I want it. Any help would be appreciated.

I am at or very near sea-level

2007 Suzuki DRZ400SM

New FMF Powercore 4

New FMF Powerbomb header

New Twin Air air fliter with 3x3 mod

Somewhat fresh motor, less than five-thousand miles

Dynojet jet kit

Stock carb

160 main

27.5 pilot

Needle in second clip position from the top with stock spacer and washer

Stock leak jet/air jet/whatever the hell it's called

93 Octane pump gas

Works Connection fuel mixture screw three turns out

I'm happy with idle, off-idle, roll-on and throttle response. The bike just doesn't seem to have the top-end it should, and pops a little on decel. Am I off on my settings, or just too picky? I know it's not a common combo with the FMF on the SM model, but the Yoshimura is just so overdone that I couldn't bring myself to buy it. If anyone has a specific or general idea of where I've gone wrong, please feel free to opine.

Thank you in advance. :)

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With that exhaust you may be a little rich on the main jet but you should be real close....

Thank you for the reply. That's what I was thinking, but a plug check a few minutes ago showed light, and I mean light, tan. One of my friends who wrenches at the local shop said maybe just a touch lean? He said the pop on decel and the lack of top-end for his reasoning. He also suggested exhaust leaks? Said something about a fog test? I'd never heard of such a thing as a "fog" test.:)

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