BSA’s first new model after WWII, the B31 was a single-cylinder four-stroke designed to be used as basic transport. The 17 horsepower engine was sufficient to get the bike up about 70 miles per hour. Normally a 348cc engine, this engine on this specific BSA B31 (VIN: XB31 8688L) supposedly has a 500cc top end and cams from a Gold Star – which is believable, as the original engine was the predecessor to the Gold Star’s powerplant. Unfortunately, there isn’t much history to this bike but it’s claimed to start and run fine. Find this BSA B31 for sale in Tucson, Arizona with bidding up to $3,650 and the reserve not yet met
