Need advice on current availability of tires.

[Lord Popgun]

Here is a cut and paste from a Google search:

180/70R-16 : This is the number that you are looking for. The first number (180) is the width of the tire in millimeters. The second number (70) is the aspect ratio, which is the height of the sidewall. The height is 70% of the width or 126mm high.

Not mentioned in the quote above, but the 16 is the rim size.

Here is the article: https://www.chapmoto.com/blog/2018/07/20...ycle-tire/