Just bought a couple Rad City STs a few months ago. I try to keep the air pressure at 55#, but I've noticed that over the course of a week, all tires will lose anywhere from about 5-15# of pressure, which seems odd. Anyone else have this issue? Should I get a Schrader valve wrench and see if the valve itself is a little loose? Pump some SlimeTM into the tubes? Any ideas on where my air is going? Thanks in advance.