A10 646cc ohv twin || 440lb || 55mpg || 105mph || 1951-63

The A10 came in three basic versions: the Golden Flash, the Road Rocket, and the Super Rocket. Many plunger-framed Flashes spent their working lives hauling sidecars, so watch out for straightness and clamp marks. The A10 engine in BSA’s swinging arm frame is arguably one of the best British offerings. It’s robust and easy to ride a long way, lacking Triumph’s fragility. The Rocket Gold Star was a super-sports version with Gold Star cycle parts and tuned engine. These can fetch £20000-plus but are highly fakeable, so be very careful; there are few giveaways to look out for. An A10 is a fine motorcycle. SRM main bearing and uprated oil pump conversion are plusses when looking to buy.