You're wanting to turn the calendar way back before the invention of the pneumatic tire? There were big and excellent reasons why the pneumatic tire was invented. A sold rubber tire will make riding a bicycle like spending time with George Foreman or muhammad Ali in the ring- you'll be beat before yo go any great distance.

Pump up the tube (out of the tire) and make sure the tube is big. Then immerse sections of the tube into water deep enough to cover the diameter of that section of tube. Then look for bubles. If you see a bubble slowly forming wipe it with your hand and watch to see if it comes back. if it does there's your slow leak. repeat with the entire tube. Also submerge the valve to check that the valve isn't worn or loose and that air isn't coming out of it.

Once you find your leak patch it. Before you put the tube back in thetire run a cootn ball around the inside of the tire and see if it snags on anything sticking through thet ire. there might be a tiny bit of glass or a fine piece of wire in the tire. You have to remove that. Also rub that cotton ball along the inside of the rim to see if there's a nick inthe rim or a protruding spoke that's eventuallt wearing a tiny hole in the tube.

Cheers

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