Ok, dumb question apparently.
Nope, the only stupid question is the one not asked
Because I'm American, not French (no offense to our French folk, my wife is part French so get over it) I have been pronouncing it with the 'S' this entire time. The first time I saw it pronounced with a silent 'S' was in a review not too long ago. Then recently I saw in a thread that its supposed to be pronounced with a "Silent 'S' ".
It doesn't matter if you are French or not, borrowed French words in English still have a similar sound. I was just talking to VirginiaJim to see if we could unpollute that other thread to which you are referring and move those postings to a new topic in THIS forum. Seems you beat us to it... at least half way.
So have I been doing it wrong this entire time?
Yes.
The "s" is and always has been silent. Of course, nobody will flog you for saying it incorrectly (at least I hope not). As you probably noticed from the other thread, quite a few people have been saying it incorrectly and many probably will continue to do so, regardless. The earth will continue to rotate...
This is a summary of the info I posted from the other thread, so hopefully all that stuff can just be removed there and kept here, instead.
The word "Concours" is well known in vehicles/racing/contests and is of French decent (French root: "a public contest or competition") and as such, the "s" is not pronounced. The correct way to say it is kawn-koor (or perhaps more Americanized as khan-kour with stress on the first syllable). Kawasaki didn't invent the word, so it is not a private proper noun with proprietary pronunciation.
The word can be examined here:
http://www.merriam-webster.com/dictionary/concours%20d%27elegancehttp://www.oxforddictionaries.com/us/pronounce/american_english/concourshttp://dictionary.reference.com/browse/concourshttp://www.collinsdictionary.com/dictionary/english/concoursPronouncing the "s" would actually result in a totally different word, the word "concourse", which is "is a place where pathways or roads meet, such as in a hotel, a convention center, a railway station, an airport terminal, a hall, or other space."
If you still don't believe history, dictionaries, tradition, and other language rules, then just go by the only three official, Kawasaki-produced videos where the word Concours is uttered:
2010 Kawasaki Concours™ 14 - Official PreviewKawasaki Concours14 20082008 Kawasaki Concours14 Movie