George, since I use my spare at least once a year, sometimes twice during a rotation I'm checking the pressure once or twice a year. I've had spares lose some pressure normally, but never had one lose that much pressure especially when new. The inflator I was talking about isn't a can of fix a flat, but one that plugs in. Either way, it's in ones best interest to check the spare when anticipating being away from civilization, but for the majority of us, a once a year check is good enough.