I've just been speaking to the VCC's BSA marque enthusiast tonight about a
couple of list members' bikes and I took the chance to quiz him about
Brandon's Ebay outed BSA.
>From the chainstay treatment, he says the bike is probably a BSA built somewhere between 1914, when this chainstay style was introduced, and 1924 when it finished. These chainstays started off on roadsters and graduated to the sports models. However, BSA found it wasn't a style they needed so it didn't stay in production for long.