Oil fouled spark plugs

I know there is probably tons of material on the site regarding this, but i'm feeling lazy and really hope that somebody will condone my laziness.

So i'm burning oil, there is a flaw in the cylinder wall. It is not something that i want to fix; i'm fine with a less than perfect bike, as long as it runs.

Problem: I rode it about 50 miles today, and the spark plug was fouled. I had installed it a few days before and did very little riding until today. I pulled it out, cleaned it off, and the bike started up perfectly. Now although i'm fine with a less than perfect bike i'd rather not ride around with a pocket full of spark plugs, lol.

I have, so far, come across two approaches to the issue: hotter plugs, and "oil foul adapters". Just wanted to know if anyone on here knows whether adding the adapter or running a hotter plug, or both, will be an issue. I know that too long of a plug will interfere with the piston, but i don't know exactly how much room i have to play with. Also, if there is any other alternative or voodoo that somebody knows of it would be much appreciated!

Oh, important info: the bike is a 1975 xl250

There is a third approach repair what is broken.  If it is burning oil to foul the plug that fast, you have a pretty big problem.  What happens when it gets any worst and uses all the oil up without you knowing it and leaves you stranded out in the middle of know where?

Edited by kmequint

Since fixing it is not an option:

There's mixed reviews on this stuff. Might be worth a few bucks to try. http://www.restoreusa.com/Engine_Restorer.html


If you try the anti-foul adapters, you might also remove the resistor in the plug cap and replace it with a piece of copper wire of the same size. Apparently, the adapters disperse the spark somewhat and cause a loss of performance, so removing the plug resistor might offest that some.


There's also the thought of changing to a heavier wt. single viscosity oil, like a 40wt or 50wt.

Trailryder: Is there an issue with using a heavier weight oil than recommended on a bike with a wet clutch? How about hotter plugs? I know that if a bike is running rich then it can help to burn off the extra gas, but will it be as effective with oil?

Did some reading on a few forums regarding people's experiences with Restore and think that i'll give it a go since like 90% of the reviews are positive. Interested to see the results.

I don't really think so. Running an air cooled engine hotter just to try to burn off engine oil is the wrong way to go I think.

The thinking in running the straight 40-50 wt oil is that the thicker oil doesn't make it past worn rings and other defects as readily as a thinner multi viscosity oil.

You might need to adjust clutch lever play.

All these ideas are trade offs and compromises, so I guess just do what works best.

Be sure to post how the Restore worked.

Edited by Trailryder42

I don't understand why you want to Mickey Mouse your engine problem. It could be something relatively simple to repair at this point. Rest assured it will not get better, and most likely get much worse, and the cost to repair it become substantially more if you continue to ride the bike and ignore the problem. Money or the shortage thereof is an issue for a lot of us as it's not cheap to ride offroad. Just don't be surprised when the bike leaves you stranded someday for your lack of care.

I just assume, given its age, it's probably a rat bike. A piece of junk, not worth doing any more to than what it takes to keep it going a while longer while you ride into the ground.

Red Dog: I am Mickey mousing" my problem because i bought the bike for $750, have invested $350, and in order to actually fix the problem, would need to invest another $400-$500. It is not entirely a "piece of junk", but i definitely do not value it enough to spend a ton of money on getting it to run perfectly. One reason being, that i would, eventually, like a bike with a little more speed so as to be highway accessible.

Ran the Restore in the bike today. Smoking is not entirely gone, but is much less intense. We'll see what happens after riding it for a while, whether things get better or go back to how they were.

Go with the hotter plug it will help.For you guys telling him to fix it,not worth it.Is not cheap to fix the old dog.Just run it till it dies.Good Luck BTR

It's a shame, it probably needs at least valve stem seals and rings, and most likely a full top end.  Probably not worth fixing. 

Start looking, because that's not a long-term situation you're riding there...

Is Restore safe for wet clutch applications? I was under the impression that the same materials in it that "fix" cylinder walls would get into the discs and cause problems. I have a large can I bought for my car, and would like to use in my bike. I think the website said to pour in in the spark plug hole?

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