Here's an interesting bike.
A 1939 HEC. "Hepburn Engineering Company", London. 80 cc 2 Cycle made by a company called "Levis".
Introduced in 1939. Well received, according to oldbike.eu. The factory was bombed in early 1940. Production never resumed. Instead HEC and Levis merged and built air compressors.
A nice looking bike, all around. What I find most interesting, though, is the intense similarity between this engine and the Russian "D" series.
Makes you wonder if the D series also had a direct ancestor.