Thin tire

As the front tire's surface was worn out , I exchanged it to new one. And I selected thin one in order to run smoothly and fast.
The change was from 1.5 inch to 1.25 inch. You can acknowledge the difference of the thickness when you see the photo.
As I continued to use tube for 1.5, it was difficult to assemble it. I'm worrying about that the bicycle could be driven without blowout the tire.