Is gas still good?

i've left mine for 2 months before and have had no issues. i think you'll be in the good, but if you feel inclined just shake the atv a little to mix the gas inside the tank. that's what i would do, but i'm too cheap to drain gas and klotz out. hehe
 
Seems that gas goes bad a lot quicker these days. I'd give it the smell test to see if still smells fresh.

Also, My understanding is that 2-stroke oil breaks down over time. So if you're pre-mixing, I would just drain the old stuff and start will a fresh batch.

Good luck!
 
I don't think a month old tank of gas is going to cause any problems unless you are using a Castor oil blend pre mix. Castor tends to separate out of suspension pretty quickly..

I would be inclined to top up the tank with some fresh stuff and go riding.