17. Facial hair is certainly not prohibited, in fact it may be extremely useful to insulate the face. This is especially practical for long-distance tours.
However in freezing conditions this may become uncomfortable.
Style, of course, is of no consequence to The Scottish Cyclist. See the full list of The Official Rules of The Scottish Cyclist.
Further reading: the Daily Record’s report of how Mark Beaumont’s beard helped his round the world record cycle.