The Belgian arms company FN was the first to make a 4-cylinder FN 1910 motorcycle. This is a 500cc engine, as big as that in the Gilera, but doesn`t look big because of the small cooling fins on the engine. These and other in line is would usually be limited by the back cylinder getting hot. When you stop, you must stop the engine and then peddle to get started again. The FN1910 motorcycles had changed very little since.
The magneto was fixed and timed properly - fuel was added - various leaks fixed and it was soon purring quietly on its stand. I rode it on some short runs and discovered it would cruise nicely on the flat at about 45 mph, although stopping and starting for traffic lights was a bit tedious, with its clutch-less single-speed setup. More specs and user manual of FN 1910 moto you can see in next overview.