Mild if tough twin that can run sweetly up to 75mph. Post ’54, with duplex frame, swinging arm, plus passable brakes, are the best bet. Tuned or thrashed engines wreck the crankshaft but there are bearing upgrades available. Tuned version, Shooting Star (A7SS), progressed to alloy head, improved suspension and full width hubs. Some really nice bikes on offer, with sensible mod’s (especially the electrics and TLS front brake).