ORIGINAL: Tired Old Man
One of my functions in temperature testing and anaylsis. If people want to waste a lot of time and effort trying to read engine temps from spark plugs, be my guest. I'll post a 200C plug pic a bit later. However, you cannot know what an engine temperature is by reading plugs alone. A data stream is mandatory. Reading a plug is best left for determining mixture settings. A perfect mixture setting indication on a spark plug is destroyed by elevated running temps.
Absolutely true. Reading plugs is no way to determine engine temp. The only good physical inspection method of reading two stroke engine temp is to take it apart and read the underside of the piston crown. Unless of course the engine is seized or has a hole burned in the piston. That's a pretty good sign of high temps....
AV8TOR