STOUT FELLOW

BSA, at the time the largest motorcycle company in Britain, got the ball rolling in August 1945 with the 350cc B31, its first all-new post war design, which admittedly, incorporated more than a few items to the pre-war range, including the M23 500cc Silver Star-inspired crankcases. The B31 also owed much to the 1940 model B29, but featured a redesigned top end with iron barrel and head which was a visual difference from the pre-war OHV singles. Up front sat a telescopic fork, a first for BSA. But before we look more closely at the B31, it is handy to look at where it came from in the lineage of BSA pushrod singles.

The very first motorcycle designed and built entirely by BSA appeared in 1910 – a fairly straightforward 500cc (actually 499cc) side-valve single with an upright cylinder, finished in the green hue that was to become synonymous with