If you think you have a slow leak in your tube, you might be right! Tubed Tires often lose anywhere from 5-15 PSI per week on their own. If your tires are becoming flat within that timeframe, or shorter you may have a slow leak! Remove the tube from the tire while leaving the tire on the rim, and over inflate the tube to locate the hole. while using the hole as a reference, inspect the similar area on the tire and rim to ensure there is nothing left behind that could cause another flat Then proceed to install a replacement Tube