Troubleshooting oil on spark plugs

[Billy]

Hey Guys,

I have this possible problem with my bike that I'm trying to troubleshoot, here's the background info:

The bike is a 1999 CBR 600 F4. I bought it in May 2005 with 10,315 miles on it. The bike currently has little over 13,000 miles on it.

Last May the first thing I did when I got the bike home was to give it a full tune up which included taking out the spark plugs and replacing them with fresh ones. Well when I pulled the spark plugs out that came with the bike, they had the normal wear on them (no oil present).

So I rode the bike around last season with no performance issues or engine issues, and this past Nov I winterized the bike and it's been sitting in my basement (heated).

Yesterday I decided to check over a couple things to make sure its ready for this season. I ended up taking out the spark plugs to check the condition of them to make sure there was nothing abnormal going on.

Well upon taking them out I barely had to apply pressure to take them out. When I got them out of the engine there was oil all the way up the threading on the spark plug and as well on the firing end but not as much.

So it's clear that for some reason the plugs became oil fouled within 3000 miles since I last checked/replaced the plugs.

Now I know this can be caused by a couple things, worn piston rings, worn valve guides, or incorret valve height.

Now considering that 3000 miles ago there wasnt a drop on the original plugs, could the valve guides, or piston rings have worn out that quickly?

I talked to some people about it and one person said that its possible that unburnt gas might have dripped out of the fuel system onto the plug, causing it to get oily like it is, but I dont understand how that's possible.

One person said that it's possible last time I started the bike I didnt get it up to operating temperature, before shutting it off. I know for a fact I did because I watched the temp guage.

So I ended up calling my bike shop and he said to put in a new set (which I did) start the engine let it warm up, ride it around a bit, then turn it off and check the plugs to see if there's oil all over them again. Now if there's oil present again after I do that what do you guys think it is? I'm leaning towards the valves but I dont understand how they could have worn out that much within 3000 miles.

[Billy]

Guys,

I got a small update, I think the oily residue on the plug might be mostly made of gas. I put it up to my nose and it stunk of gasoline.

[Degsy]

Gas leaked in over the winter.

[stoinkythepig]

It's possible the valve cover gaskets in the plug wells are seeping and the oil has only one place to go. I would not worry about this at all. You have a terrifically reliable engine there with really low miles. Just go ride it. Oh, save the old plug$, they probably have another 20,000 miles left in them.

[GMAN226]

IT's a honda, there is nothing wrong with that motor.. Just ride it, it will be fine. I raced the same bike with the same plugs that came from the factory and that bike had over 10K on it.. And it still made better power than Degsy's..

G-man

[Degsy]

Yes it did, bastard!!

Better than my F4 that is, not the F4i

degs

[GMAN226]

Originally posted by Degsy
Yes it did, bastard!!

Better than my F4 that is, not the F4i

degs

True dat. You hear from Peter yet?

G-man

[Billy]

Would it be ok if I sprayed a little carb cleaner down onto the threading on the aluminum block?

I just want to clean the crap out of the threading so when I put the new spark plugs in they stay nice and snug.

[stoinkythepig]

Originally posted by BadBoyBilly
Would it be ok if I sprayed a little carb cleaner down onto the threading on the aluminum block?

I just want to clean the crap out of the threading so when I put the new spark plugs in they stay nice and snug.

probably would not hurt anything but it's not necessary. Just put the new plugs in snugly and ride. They won't loosen.