KDX200 slight misfire

[Hoffies]

I have a 2006 KDX200 and really pulls well. However when I climb off the throttle or no load on engine(bike is up to speed and no longer accelerating, engine has slight misfire. Even at WOT has misfire every few seconds. I have played around with main jet and needle as thought it may be running too rich but misfire prevails. Does the air screw have any affect above 1/8 throttle? Plug core deep inside shows more black than brown(plug chop at 1/2 throttle). Any suggestions?

 

[KDXruss]

Spark plug gap too wide?

 

[767Capt]

Try dropping the needle clip one slot?

 

[4thGearAndPinned]

elevation and ride temps needed...

 

[Hoffies]

Temperature range between 25 and 35 degree Celsius aprpox 1000m above sea level. 155 Main 48 pilot 2 clip from top needle, FMF pipe.

 

[KDXLance]

My Bike had a similar problem when I was experimenting with jetting after break in from new. I dropped the needle to 3rd from top and it fixed ok. I thought it was more a popping noise when throttleing off from being lean somewhere rather than a misfire.
155 main, 45 pilot ,mid clip, pro circuit, airbox lid tossed. This was the set up i settled with.

 

[John Harris]

my experience and observation shows that if you use 155 main, 42 or 45 pilot, and clip close to top (probably second from top) you will be close. You can adjust clip and air screw for finer settings. My opinion is that your pilot is too rich and you bike slightly hesitates as it cleans itself out. Cheers John