1990 K100's stalling issues

I own a 1990 K00LT which I purchased with only 26K miles.
I live in the very bottom of the state of New Mexico and we
certainly get very hot, hot summers. Two years ago I went
to Colorado Springs and last year I tried to make it to Sedalia.
On both occasions, the K bike stalled, losing power little by
little and finally quit running as I went from 70mph to 20mph
when it finally quit altogether. I changed s/plugs, s/plug wires,
fuel filter, and disconnected the computer plug several times.
The problem persisted, but only during the hot summer months;
never during the cool weather. Then I read an article in the
"Motorcyclist" magazine about ETHANOL-and the bad effects
on high compression motorcycles.
Thereupon, I purchased STA-BIL ethanol treatment. I add two
ounces of this product to each fill up. Three trips so far this
past 2013 summer-each of 350/400 miles and the bike has
run great.
Conclusion: the small amount, 10%, of ethanol will form at the
bottom of the fuel tank and when it enters the fuel line, this is
causing the vapor lock. Hope this helps other K100 owners as
the motor was advertised as "The Million Mile" motor by BMW.

Stabil makes decent stuff; also keep your eyes open for another juice called Star-Tron, a blue liquid, comes in a little plastic bottle. Many bike dealers (and most auto parts stores) now carry it.

I've also heard (but cannot verify) that sometimes the fuel that is returned to the tank is very hot, and this contributes to poor running. One friend installed a little power-steering cooler into this return line to significantly reduce this issue, and also the heat flowing back onto his thighs.

I am thinking that the conclusion may over simplify things. I would suggest that it might be good to use/carry for use an amount of additive to ensure the fuel you have and/or get stays properly mixed. Separation of the OH from the gasoline or the adsorption of water each will cause issues. In 25 years and 250,000 miles of running K's in all weather extremes and elevations, I have never experienced this issue, but I have accidentally introduced fuel with apparently unblended water and or 'dirt' which caused minor issues or filter clogging respectively.