Keeps Fouling Sparkplug

[JMiller]

I just rebuilt my 87 KXT 250. I decided to rebuild because it was smoking and fouling the plug after @ 8 min. of riding.It would start to kinda load up then no power and eventually stall. So I yanked apart the motor, replaced the crank bearings, crank seals, piston, rings and,all other seals.
Now I take it out for the first time and it does the same thing after being rebuilt. The carb is spotless. I did notice my needle on the slide was bent at the top, icould this be the cause,. Should i get a new carb? Do you guys think this is a carb or fuel problem? The fuel I used was fresh. here is a pic of the plug. Any help is greatly appreciated.

[Tri-Z Pilot]

That plug doesnt look fouled, you must have the notorius tecate stator problems, I bet that after the bike cools down, you go and start it, it will run like a champ for 10 mins, then start to die.

[Lots_Of_Nothing]

looks to me like your main jet is too small

[JMiller]

It will start right up when i replace the plug, even right after it dies. It also seems to smokes alot.

[JMiller]

If the stator were going bad, is there any way to test it? Also, if it was the stator, would that cause the plug to foul? When I pul the plug after it dies, there is dark liquid around the plug, it is thin like fuel, is this fuel? Please help!!!!

[J.D.]

That pic of the plug you pulled, did you clean it up first or is that straight out of the engine? If you cleaned it that won't let us see what's really going on!

[sportvette]

i vote stator. but i dont have the bike to tell. has the stator ever been changed? as far as i hear they go bad all the time and not good to replace it with the same oem type.

http://www.rickystator.com/pages/Tecate3_Stator.html

i will buy one of these when i have trouble with my bike. that wont be until i actually get it back together. so it wont be for awhile.

thanks,
mark

[J.D.]

Actually now that I think about it I'm leaning towards stator/flywheel problems. When my Tri-Z ran, my stator plate screws came loose and it was bouncing around and throwing timing everywhere. It would continuously eat plugs every 10-15 mins or so, and like you if I threw a new plug in, she'd fire right up and go another 10-15 mins. Good luck!

[JMiller]

The stator has been replaced @ 8 years ago. My stator plate is tight and in the position it should be.

[J.D.]

It could have went bad in that time! Are the magnets still glued on the flywheel? I hear all the time how they come off due to cheap glue.

[TimSr]

If thats the plug, as it came out of the bike, its not fouled. It looks like its not getting any fuel. Right after it dies, check for spark. When a stator goes bad, you will either have no spark at all, or it will spit and sputtter really bad when its running. If a new plug solves the probem, even temporarily, its probably not the stator, but switch plugs back and forth to make certain its consistant that the plug has failed, and a not a result of your changing position of the plug wire when you replaced it.

Also check fuel flow all the way through Pull the line off of the carb and turn the gas on. If its good there, reconnect to the carb, and then open the carb drain and turn on the gas again. This will assure that its flowing through the float needle and seat. If you get a stuck or clogged needle and seta, it may run fine until teh bowl emties, and then, just by having it off for a couple of minutes, enough gas enteres the bowl to reume running until the bowl again empties. A float set too low will give the same symptoms.

[JMiller]

But where is the smoke coming from?

[J.D.]

What color smoke is it, Black, White, or Blue?

[JMiller]

More of a white color

[J.D.]

Well without describing "blue" smoke to you, this leaves us with two options. Blue smoke to the untrained eye would probably look like white smoke, but it has a bluish tint to it, not completely blue like the sky.

White smoke means your sucking coolant into the cylinder.

Blue smoke would mean oil. Does it smoke after it's warmed up good?