Bikes have two types of inner tube valves, Schrader (like a car tire) and Presta (not like a car tire). A bike set up for one cannot use the other.

My new bike had a slow leak in one tire. It went flat after 3 days. Then after 2 days. I used every trick in the book, but I couldn’t find the leak. No trouble. I had a spare inner tube in my emergency kit and a second in the cupboard. No doubt you see where this is going. For some reason, it took Amazon 4 days to send me new tubes. Trikes often have small 20″ wheels. They don’t sell many 20″ inner tubes. But really, 4 days??? Anyway, it looks like all three tires are good, and I now have the correct spare inner tube in my emergency kit. I am very happy I didn’t discover this when I was 20 miles away from home.

I hope this finds everybody doing well.