I have several WW2 BSA M20 military motorcycles. When they came off the BSA line,everything was painted a flat olive drab,except the engine. The castings were not polished,however-just rough and dull. After they had been in service a while,they got repainted many times. One of my bikes came to me straight out of gov't service-every bit of it was painted british bronze green-even the carb! The whole bike looked like it had been painted with a mop,too.