1937 Pre-War BSA B21 Sports Rigid Girder 250cc OHV. Frame number, HB20 6999. Engine number, HB21 2285. This model was only made for one year, making it quite a rarity. It is a light motorcycle, easy to handle and move around. The machine was restored some time ago, with the engine fully rebuilt, bottom end refurbished by a well-known Gold Star specialist. Good replacement barrel and piston were fitted. The bike has been fitted with a three-speed gearbox, at some time in the past and this works fine. This BSA has been sensibly modified to allow the oil tank to accept an additional and cleanable oil filter. It also has a manual anti wet-sumping valve fitted. The gentleman I bought this machine from had owned it for 20 odd years and had done all the work previously mentioned. When I went to view the BSA, it started easily, ticked over, ran and sounded OK. I have not started the engine for a year, due to my age and gammy leg. The bike will probably need some recommissioning. I am now looking for a new custodian, who will enjoy the bike as much as I have done.