fouled plugs

[woodsrider823]

Hey I was wondering if a fouled plug will fire outside of the bike like when it is still attached but is near some metal. I can see a spark so does that mean the plug is fine? how do you tell if a plug is fouled? When i take the plug out it is coated in oil, whats that meen?

 

[Green Hornet]

"I can see a spark so does that mean the plug is fine?"
That means you are getting spark. Thats a good thing.
Is your plug wet looking, oily looking??
A small ring at the bottom of the ceramic insulator is what you are looking for (Proper Jetting)
The ring size-1-2mm, I believe.
Anyone want to chime in??

 

[woodsrider823]

yea the plug is wet looking when i take it out.

 

[GS]

Several times (over 38 year...GASP! )I have had a wet looking plug fire(arc) pretty strongly while outside of the engine, but fail to fire the motor. Replaced with a new plug and fired up on the 1st kick.
My theory (FWIW) is that under load(compression) it won't quite jump the gap. So...seeing a spark is not a guarantee that the plug is OK. That is a fact!
It's wet because the engine is getting gas/oil, but not burning it off. That wet juice (I believe) provides an alternate path for the discharge....meaning an inadequate ignition source for the fuel.
Nothing quite like a FAT blue spark!

 

[crazyrydermx]

You shouldn't have to worry about a fouled plug anyway unless it is disrupting the bike somehow (like if it won't start or something)

 

[kmccune]

The easy answer is to check the jetting.

 

[TimberPig]

Several times (over 38 year...GASP! )I have had a wet looking plug fire(arc) pretty strongly while outside of the engine, but fail to fire the motor. Replaced with a new plug and fired up on the 1st kick.
My theory (FWIW) is that under load(compression) it won't quite jump the gap. So...seeing a spark is not a guarantee that the plug is OK. That is a fact!
It's wet because the engine is getting gas/oil, but not burning it off. That wet juice (I believe) provides an alternate path for the discharge....meaning an inadequate ignition source for the fuel.
Nothing quite like a FAT blue spark!

This explains it right here. Replace the plug if it is suspect. Unless you get the very rare defective new plug, it should cure your problem.

If you are having frequent fouling issues, your jetting is likely a bit rich, and could stand to be leaned out some, which will cure the fouling problem. Even with proper jetting, you may foul out a plug, but it will be much less frequent. When properly jetted, they very rarely foul spark plugs.