You must have amazing lungs, I never get amazing clouds not on 2 nor even on 7 because if I try it on that temp the taste has become so bad that my throat can't take it!!!
I mostly have it on 3 when using just my flexible stem, but when I use any of my bubbler's it has to go to 4/5 because of the water cooling the downstem, so more power is needed than.
To vape with just the stem on higher than 3 is out of the question for me because of throat issues, somehow my throat is very sensitive to hot air.
Never had the problem while still smoking.
Flexible Stem? I have never heard of that. My solo clouds like a mofo above 3 - not for long as the load sizes are small but I have never had an issue milking a solo. I agree that above 5 or 6 it may be hot enough to irritate ones throat but if I may without sounding direspectful - please follow me....
If your getting hot air out of your stem, or at least hot enough to bother your throat then I would say IMO it sounds like its NOT a mechanical issue. What it sounds like to me is your weed and I will tell you why. All of us non MMJ state people have a back up guy in case our usual "supplier" is not around. I had some fucker in Florida sell me what looked great but was in fact awful herbs. When I vaped it, regardless of temperature I got NO VAPOR! Again, no disrespect to you or your supplier but is there a chance you got some bad weed?