I am used to riding cheap walmart ligh weight bikes so I don't know if this is common or not.
Is it normal for air to escape from the tires when you are not riding them? I left my bike alone for a little over a week because it was stormy outside... within that time the tubes went from 55psi to 25psi. I don't think it is flat since I bought thorn resistant inner tubes and I have only ridden it a few times since then.
My bike is a 1972 steal 24 inch, and I was wondering if the weight of the bike was causing this or if it was just a slow flat.