Originally Posted by The Golden Boy

The 27" wheel size is obsolete. It is no longer in common usage- there are no major bicycles in mass production that use the 27" wheel size. That's a great example of obsolete. The tires that are currently being produced are pretty much only for existing bicycles with 27" wheels. Obsolete.

obˇsoˇlete
ˌäbsəˈlēt/
adjective

no longer produced or used; out of date.
"the disposal of old and obsolete machinery"
synonyms: outdated, out of date, outmoded, old-fashioned, démodé, passé, out of fashion;