- Aug 19, 2003
My brother has a KX 250 1996 which was good for about 6 months when it started to loose a little power. He stripped it down over the winter to "do it up a little". When he put it back together with new rings, piston and reboard barrel it started burning out spark plugs. This led to lots of smoke. Know it just smokes alot. The carb is fine. He thinks it may have a warped cylinder head. The thottle cable is also good.