Engine problems on a kx 250 2 stroke

White smoke is usually burnt water.
Check your radiator water level, if it is down, check for a blown head casket in your engine e.g.(water in the engine oil, or oil in the radiator water) brown froth on filler caps.

this case , you have to check turbo charger , when high RPM white smoke means lubricate oil goes to engine so give white smoke . on low rpm trubo close coming black smoke means no enough air gose to engine so this need to replace turbo . some type of turbo can be clean the wase gate ( which open with diafam beside turbo) make sure it's moving when accilerate. check vacum is ok . then clean wase gate > only some type have wings inside )if no replace turbo

check the air/fuel mixture

im presuming its a two stroke it sounds like the two stroke oil pump-which is starving the engine of oil-change the pump before u destroy the engine-this is not a maybee,your engine will need a total rebuild if u carry on riding with this problem!!!!!!!!!!!!!

This is normal for a 2 stroke and not a problem at all. It's just a build up of 2 stroke oil that acumulates i the the packing in the muffler.
Nothing to worry about, and no solution to fix it really. You can re pack your muffler with clean packing, and try running a little less 2 stroke oil in your mix. I would recomend using a synthetic 2 stroke oil, with a mixture of 50:1 this would prevent some of the mess from happening.

The standard mix is 4 ounces of two stroke engine oil to one gallon of gas. Do not use standard motor oil. Only use two stroke engine oil.

The exhuast valve set-up on a performance 2-stroke operates only at higher RPM.

Your discription sounds like the engine has a seized piston or two or three. Pull the head and look and feel inside each cylinder. The cylinder walls should be super smooth and have no scratches. If a wall is scored up then a seizure has happened. Seizures are due to excessive heat. A lack of two stroke engine oil in the gas is possible as well as a bad water pump. NGK BR9ES is the stock spark plug.

Use TWO STROKE ENGINE OIL in the pump. If not using an automatic oil pump, then mix the gas and oil 32 to 1. That equals 4 ounces of TWO STROKE ENGINE OIL to one gallon of gas. NEVER use motor oil in the gas. Only two stroke engine oil.

"Learn to like smoke for awhile. Smell the aroma". Pardon the humor. I couldn't resist. Chances are there is oil built up in the crankcase. It is going to take some time for the oil to dissipate. How long? I don't know. It all depends on how much is in there. Cleaning the muffler is no help since the oil burning is coming from the crank not the muffler. If you are careful, and keep a vigilant eye, you could cut the gas/oil mix in half to 64 to 1 instead of the normal 32 to 1. That would mean only 2 ounces of oil per gallon instead of the normal 4 ounces. Let the crank add the rest. This will help burn the crank oil excess, but BE CAREFUL. When the crank drys up you had best not ride until more oil is added to the gas.

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