4weeks & it's already on its way to being stuffed.
Google it if you don't believe me.
Please believe everything you read on the interwebs.
Gas does NOT deteriorate after 4 weeks as this dude says. Now, If it was in an open air container then yes, it would be on its way to getting crappy.
But in a closed air tight system where air cannot freely go to the gasoline, it can last over a year no problem.
I know people that used like 4 year old gas with no problems because it was in a sealed 1000 gallon gas container. Hell, I even filled my bike up while I was there and seen no bad side effects. (Filled my 125 scooter not the 250 CBR.)
Yes gas can go bad sooner, but the point is, in our gas tanks it can sit for a long time and be fine. People that buy into that gas stabilizer stuff makes me laugh to myself, but I don't care how people spend their $$. Yes stabilizer is good if you do plan to store it for a long time, but doesn't make too big of a difference.
PS: This is not including Ethanol gas. You can't even buy that garbage around where I live, but if you go the next state over you do find it..
TLDR: The only way gas will deteriorate quickly is if its not in an air tight container, or if it is ethanol. Normal gas will last years as long as its stored properly.
That does explain it well.