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Bogging issue !!! Need help

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I have an 06 kx 100 recently had the top and bottom end rebuilt. After the beak in I  decided to put an FMF exhaust on Shorty silencer and fatty expansion chamber. First ride seems a little sluggish in the mid range and did not do so before I put the pipe on  so I raised the needle clip  position up one notch from position 4 to 3 to lean out the mixture it seem to help a little bit now the problem I’m having is that when the bike is started and warmed up it bogs when I open the throttle quickly at idle then it will rev high  immediately after then go back to idle. The main jet is stock at #138 pilot jet is stock at #45 fuel screw is set at 1 3/8 turns out from fully seated . I’m running 32:1 pump gas 93  octane I’m at 200 ft above sea level. Weather conditions are about about 32 to 40 degrees  fahrenheit. Spark plug is a dry looking black coating but does not look like it’s dripping wet with oil.  Any recommendations to how I could fix this bog issue would be greatly appreciated thanks 

Edited by Dcg12345

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@William1  recommendations call for main #140 pilot #48 stock needle 3rd clip position 1.5 turns out .. correct me if I’m wrong but wouldnt that make my bike run richer when it is already running on the rich side ? From my understanding pipes make your bike run more lean.  Forgot to mention I also have a bit of oil running out of the end of the silencer as well 

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Running in the air screw richens the mix at and just off of idle.

Pipes only lean things whn in the area the pipe is tuned for. Other rpm ranges can richen or lean out. There is a reason they suggest jetting. On a 2S, there do tend to err on the rich side and then as a rider, you are expected to test and get to the to the final setup.

Needle changes are extremely tiny and rarely make much of a difference, three clip positins at once does.

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If the air screw doesn’t help Should I try one step leaner on the main to help with the spooge and spark plug color ?

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10 hours ago, Dcg12345 said:

If the air screw doesn’t help Should I try one step leaner on the main to help with the spooge and spark plug color ?

No. Main only comes in to play with the throttle about 7/8ths.

Instead of guessing, read up on jetting, try the rec. specs and test carefully, starting at getting a good idle, then moving up from there.

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