The "L'AEROPHILE" magazine nr.10 from the year 1908 showed a photograph with a racing car engine of this brand that was also used on an airplane, so we can see in the picture below from the Edouard Chateau collection.

“Bayard-Clement 123 CV engine” (PiP)

-The man holds a Chauvière propeller.

-And here a 200 CV Bayard Clement for airships presented at the 1909 Paris Air Show. Model with overhead camshaft, what we would call today OHC.

"Bayard-Clement 200 CV engine"