Was having a discussion with my son-inlaw, who is a very good motor cycle mechanic, regarding cylinder temperature. He uses an infra-red temp gun to measure each individual header temperature at idle, 3000 and 4500rpm to check the mixture when each jet cuts in at those rev ranges.
These temp guns are very accurate and quite handy. I ordered one off ebay. $A33 delivered to my door and had a play with it this afternoon.
The difference between all 4 headers shouldnt be more than about 10 or 20 degrees C.
and it aids enormously in reading a good air/fuel mixture to each cylinder.
Lean mixture obviously means hotter burning.
Probably other members use this method of tuning but to me its new technology and very interesting.