Acquired this bike over 30 years ago at the Ann Arbor Bicycle Swap Meet from a gentleman who had been the New York importer for this motor. This add on motor was made by BSA motorcycle works, economical bike motor units like this were prevalent throughout post WWII Europe. As Europe's Economy rebounded they lost there popularity. The winged wheel was a single-cylinder two-stroke engine whose gas tank doubled as a rear luggage rack, the over-sized rear hub houses a set of chained reduction gears and a very powerful drum brake, the unit is mounted on Rudge bikes of the same era. The bike is all original.