Pumps

Why do bicycle tires loose air even though I know I don’t have a flat?

Bicycle Tubes/Tires are known to have noticeable air loss after about 2 to 3 weeks. This is because small air molecules are small enough to seep through microscopic holes in the tubes.  Great example is a balloon.  Try leaving a balloon fully inflated.  In about 1 to 2 days you should see a significant amount of change in size.  The thinner / less dense a container is (anything that holds air), there is greater air loss.  And also the smaller the tubes are, there is going to be more noticeable drop in pressure since there is less amount of air.  So if your wondering why your bike is loosing air and your car tires aren’t, it’s because the thin skinny tubes in our bicycle tires act as a container for air.  Where a car tire is tubeless and is a lot more dense, and also A LOT more air in them for you to notice any type of loss in air pressure.  Also if your wondering why one wheel looses air faster then the other, is because of the inconsistencies in inexpensive tubes.  Easy way to tell if you have a flat or not is if you notice a drop in pressure after 1 to 3 days of after putting air into the tubes.  If the pressure is lower, then you have a flat.