BS Production for 1937 was as follows, 45 of the 11/50 JAP model, 18 of the SS100 with Matchless engines and 110 of the SS80 with Matchless engine
The 11/50 had changed slightly in that the magdyno was now chain driven, like all the other models, levels were more likely to give problems in wear and noise if not exactly setup.

A new arrival for 1937 was the BS Petrol Tube Sidecar, a large diameter continuous loop steel tube frame, with all the attachment and body points clamped on to the tube. The body was carried on car type leaf springs fore and aft.The body was usually the BS "Cruiser" type that had been in use for several years. The tube could carry petrol to about 2 gallons when the main petrol tank became empty a tyre pump was used to pressurise the tube and expel petrol up a rubber tube and into the bike tank.