plug chop? you saying that was a brand new plug before the run?
yea, the thread got greasy when i pulled it out, im just talking electrode insulator cover
Ideally a plug will appear brand spanking new after a plug chop..
Insulator is white and smooth and clean (NOT grey, not microscopically pitted and no signs of tiny aluminum speckles which indicates transfer of metal from the piston or head to the plug.)
Electrodes edges are sharp under magnification (not rounded over which is a sign of melting)
And there are lot of other indicators.. But it's obvious that your plug is not getting hot enough to burn off all oil and fuel residue. If this happened, as you say, on a single run on a brand new plug, I'd suggest the mix is rich or the plug is too cold or, for some reason combustion temps are very low.
But i still have a hard time believing this plug chop was done properly.. it looks so bad that i'm thinking you allowed the engine to idle or the engine wasn't first allowed to reach normal operating temperature..
i thought that if you didi a plug shop w/ a new plug and it came out crystal white that it meant that the engine was running too lean. and that a nice cofee brown after about 10min was perfect.
I used the engine cut off switch and braked hard to a stop then immeadataely pulled the plug.
am i wrong in the coloration thinking?
Humm, i know joew is normally right but....
this plug shop looks right to me.
IF the insulator stays white after a plug chop, the engine probably has no oil or too much air.
The light cofee brown color is great, almost perfect to me.
I'd like some other opinions to be sure, but my experience (the little i have) tells me it's great.
The insulator on an old plug get discolored. This is normal. But new plugs are used during plug chops to reveal only what's going on right now..
What I see in the photo on the brand new insulator is burned oil residue. This indicates the plug heat-range is too cool to keep itself clean. And i see what looks like soot around the plug's outer edge.
Unburned gasoline leaves soot. Soot is black, not brown or any other color. Soot will tend to collect first down inside at the bottom inbetween the insulator and the metal shell of the plug... deep in the coldest area of the plug. If you see soot down there the mix is rich to some degree.
The perfect fuel:air mixture cannot be directly read from the color of a plug.. the reason is only logical.. With a perfect mixture there is nothing left to color the plug. Fuel burns completely and leaves nothing behind. Ideally, for maximum power, the mixture is perfectly balanced.. No extra gasoline molecules and no extra oxygen.
Color would come from oil.. and the correct plug heat-range would have burned all that oil away.
A TOO-lean mixture first reveals itself by various sorts of physical damage to the plug. Insulator surface is a burned-grey and pitted.. electrodes show signs of melting at the edges.. However things like the correct ignition timing advance and plug heat range must be settled before the fuel mixture can be accurately read off the plug..
From my vantage point, your plug is lightyears away from showing signs of being dangerously overheated by a lean condition. If you want to develop maximum power you gotta get a little closer to the racer's edge..
Here's a pretty good PAGE on selecting and reading plugs.. most of the plug reading stuff starts about halfway down.
On a touring bike that plug looks ok to me too.. So what if the mix is a little rich or if the plug is too cold? The thing will run fine and it'll run forever without any chance of overheating under normal riding conditions..
but if you're talking about high performance, where people spend money deliberately modifing the bike and care about developing max power and take the time to fine tune for performance, the results of that plug-chop leave tons of room for improvement, imo.
I'd take that plug chop after 25 miles, but 2 miles? It's gonna build up a lot of crust the next 500 miles.LOL!
But like Joe says, you aren't running lean and you won't burn a piston UNLESS you don't get enough oil-injected.
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