Seriously?...Part of the reason I inflate my tires beofre every ride. This also tells you if you have an upcoming problem. If Saturday's infation was to 120 and Sunday morning your tires are at 80, there's a problem, maybe a slow leak that's going to get you on the road.

You should also get a gauge to check the tires. I use one to compare/ calibrate floor pump gauges since they are known to be inaccurate. Aftra few times, you get to know the pump gauge, but it's good to have an accurate hand gauge anyways.