Dead Spark Plug - All ok Though?

[KevTM]

This is a weird one for me. One of my spark plugs died, thing is though, it's all fine, great electrodes, no wear, no fouling, no cracks, no heat damage etc etc.. good blue stark from electrode.

It's definitely the plug as i switched it with another from another cylinder - the then faulty cylinder worked and the then working cylinder not firing. Tried another plug out my other bike and it runs on all four.

Thought it may have been the crush washer? tried giving it a clean up and doesn't seem in that bad of a condition..

I'll get another plug obviously but just wondering why it would die like that overnight? I don't use the bike and the garage seems to have a bit of condensation in it but i can't see why this would affect only one spark plug (or a spark plug at all). I might hit it with a blowtorch let it cool and try it again

[The Artist]

Spark plugs are consumables, they break down inside. Sometimes there is no visible damage.

They are only a few quid so don't worry about it. If it is one with a resistor inside, that could be it aswell. (the code will be in blue if its NGK)