i have stored it in my garage for up to 25days and it was fine. i don't remember at what rate the battery dropped but it was insignificant. charging it to 80% should be more than enough. Tire PSI depends on your tire size. again 45 days is too short to notice any change i think. i stored my 21" for like 6mos and it was below the recommended threshold when i installed it again but it wasn't too bad. it was still drivable, this time i over inflated it before taking it out and storing for winter.