What is the engine surface temperature of a NC23 engine?

[Mansie]

Hello, has any of you measured the surface temperature on the barrels of a running engine? I would imagine that the engine is hottest near the hot gas exits where the exhaust manifold attaches. The NC23 engine is the inline 4, shared between CBR400 and CB400 with minor variations.
I am asking because I was thinking of having the barrels powder coated but when I spoke to Aerocoat they were worried about how hot the engine would get. What they said was that 200°C would be fine, but 400°C definitely not. The NC23 is a water-cooled engine so I would not expect it to get too hot. I have seen pictures from other powder coaters doing the barrels so maybe it is just Aerocoat not being comfortable doing it?
Cheers, Mansie

[Gidanski]

Coolant and oil temps would be are generally below 90-100 degrees in normal operation, And there would be no where near enough radiant heat from the extractors to be of concern when riding along. Only point of concern would be anywhere in direct contact with the headers.