2012 kx250f low end bog

[1015]

My bike has a bog at low end .in just about any gear.new tps.valves in speck.injectors good.fuel pump at pressure.clean.new cylinder and piston this spring.at Kawasaki dealer as its over my head I guess.they can't find out source of problems ! Anyone have this problem ?

[ox715]

Is it just on the low end or all the way through? I have a bog but it's almost always throughout the complete RPM range. Still haven't figured it out either. 

[Amooseondaloose3]

Ox715 what size is your main jet I bumped mine up to a 180 and it made a difference that I couldn't believe

[ox715]

Ox715 what size is your main jet I bumped mine up to a 180 and it made a difference that I couldn't believe

It's a 2012 so it's the FI model. I actually think we've narrowed it down to the timing chain jumping a tooth. I installed a new chain... But I busted the camshaft cap torqueing the bolts down. So, I haven't been able to verify if this has me straightened out or not.

[scuubyduu989]

You problem know this if the. . . Dots look like that you are good to go. I've read that if both on top it will run both on top it will run but if both are differant bad day. Good luck

[scuubyduu989]

I ment to say both on top it will run both on bottom it will also run but if both are differant won't run right

[FaceDeAce]

My recent experience says to look at the cam lobes first and foremost, over looking at the dots second. Apparently these cams can slip the sprocket gear on the shaft and go out of time. My symptoms (on a new2me bike) were a severe bog. Low on power. Sporadic hanging idle. Behave as lean running. Found the intake cam had slipped. I put a thread up called "camshaft indexing". May or may not be your cause. May or may not be helpful. But there you go, something to check.

I was surprised [emoji15] . I kept going at the carb looking for an issue internally with the pilot and leak jet circuits. Wasn't there. Found this slipped sprocket. Fixed the cam. The bike now Rips. Barky and really snappy. No bog. Tough to hang onto the bars and keep my seat on and front tire down now!

Other than cam timing, for a bog look at your accelerator pump timing, AP diaphragm, and leak jet circuit for blocks.

Hope that helps!

Edited September 27, 2016 by facdeace

[Cbadami]

I have a perfect set of cams if you want to buy