Overheating and fading - means what?

[thegrouch]

Many times in e.g. Haynes manual or on websites one can read that lean mixture can lead to overheating, or that if engine "overheats and fades" one must check mixture or carb inlets etc etc.

My general question is how to really distinguish "overheating and fading" from i.e. fuel starvation? HOw to check that engine is really overheating? Is the spark plugs test the only way? Besides I think I haven't seen any reference temperature in the manual, i.e. oil temperature, so it seems to be kind of "feeling of overheating" or?

Any ideas folks? Maybe someone did some tests (oil temp?)?

 

[xschris]

I have a IR temp gun that I use to check engine temps. Anywhere from 265 F to 290 F depending on air temps and how you ride it is what I get with my two bikes. Those temps are taken at the head on the exhaust side from the plug (hottest part of the head). Other parts of the engine are less and very greatly.

 

[drewpy]

if its really overheating, the oil starts to smell as it tries and cools the pistons etc.