I looked through the brochure for some explanation or even references to cock fighting or roosters or chickens or even poultry in general, but there’s nothing. Just some festive cover art of a couple of chickens, one dead by the other’s beak. I think Triumph’s current ad campaign has moved away from cockfighting imagery, but who knows, maybe it’ll make a comeback? I mean with modern CGI, you could really make a graphic and realistic motorcycle-based gigantic chicken fight, right? UPDATE: It seems that the cockfighting artwork was also used on the 1927 Triumph owner’s manual, and is referenced in this video, where someone had it painted onto their gas tank:

As it happens, the northern Flemish part has a lion as the regional symbol, and the French speaking southern part has a rooster (or cock, if you prefer) as the regional symbol. Pure speculation on my part, but this could have been a Wallonian (the southern part of Belgium) ad and edition of this motorbike. (p.s. Our two communities live together peacefully, even if some political agents try to divide and conquer – but in 1929 I can image this symbol to have strongly appealed to national and regional identity in Belgium.) Pretty lame if it’s just a gimmick for extra clicks. That’s about as useful as new paint on a David Tracy jeep. -from a former Arizonan, where cockfighting was legal through the 1990s.

What The Hell  Is This A Cock Fight In An Old Triumph Motorcycle Ad   Cold Start - 94