I am having a problem with my bike idling correctly and having been searching threads for help.

I have a 09 klx250s I have the FMF power bomb with q4 and the uni-filter as well as a dynojet stage 2 installed. The bike will start fine but I cannot get the idle to stay consistant. It will start and idle at around 1400rpm sometimes it will jump to 2200 or so then eventually slow down to 1400 again. While driving and coming to a stop it will hang sometimes around 3000 rpm sometimes it will settle down as normal. I sprayed around the carb to check for leaks and cannot find any I have the air mixture screw set to 2.5 turns out. I live in PA so I am about 400 above sea level. I am sort of at a loss here on what to do.

 

Play with your choke plunger a bit to see if that helps / has any effect.

The throttle plate certainly won't be moving on it's own and you'd likely feel a sticky throttle. That leaves the pilot circuit.

I'm no expert, but maybe check your float levels too.

What jetting are you running with that big exhaust? Are you running with a snorkel or anything?

 

128 jet and the snorkel is removed I had the carb out to set the float level and that made a night and day difference starting the bike

 

Well let me paint a picture and offer an opinion - So you bought the bike new, you have done all the wrenching on it yourself, It has been running perfectly for quite a long time but suddenly started this idle crap.. There is no way you caused this because you haven't even looked at it crooked much less wrenched on it in quite a long time.. There was no warning on the current issue - it ran great one day, then didn't the next.. It'll just sit there idling fine, then zoom up to 2200..

If all the above is correct - tap the float bowl with something metal when it zooms to 2200.. If the tapping makes a difference, it's a float system issue..