This is one of Caille's "B" class race motors for 1929, which they named Champion.
It has only one carb, unlike its brother, the Flash, which had two.
On the motor in the 2 photos please note that it has
the wrong air horn.
It does however have the long racing tiller with the throttle twisty bit (the knurled metal part aft of the rubber grip).
Note the nice decals. All in all a very nice example.