⚡ Quick Answer: The 1968 BSA A65 Lightning is widely regarded as the best year BSA to buy. It represents the pinnacle of the twin-cylinder A65 engine's development — refined oil-tightness, improved carburetion, and stunning chrome work — before BSA's quality began its steep decline in the early 1970s. It offers genuine reliability, plentiful spare parts, and strong collector appeal without the eye-watering price of a pre-unit model.