When I visited the Château de Savigny-les-Beaune during my tip to France in May, I saw a couple of 'Tigre' motorcycles in their museum. I think there were two solos (one racing) and a sidecar.
When I got back I did a bit of 'digging' around the Web, but turned up very little information. The engine was built by French company Panhard, at one time a car manufacturer but now build military vehicles. It's a 851cc flat twin of 'about 50 bhp' that was used in their 'PL17' car built in the 60s.
A blog I found gives a small amount of information plus some photos:
There was also one in the museum in Reims that I visited later on that trip, but I've no idea how many more were built.
Here's an extra treat for you. When I was looking for details of this bike, I found an example of the car that donated the engine, the Panhard PL17 on French Ebay.