1939 Norton Big Four 633

, Great Britain. The Big Four 633 was outfitted with a one-cylinder, L-head, 633-cc engine having a physical size of 82 by 120 mm. Originally it was a belt-drive model, but somewhat later on, in 1915, it was replaced by the chain. In 1932 the right-side exhaust line was designed and next year a 4-speed gear box. #norton #big4 #ww2 #worldwarii #worldwar2 #military #army #ukmade #madeinengland #britisharmy #vintagemotorcycle #vintagebike #bikestagram #instamoto #instabike #offroad #swd #history #antique #retromotorcycle #classicmoto #vintagemoto #classicbike #britishbikes #1930s #1939 #motor #moto #633 #motosofwar