In a sweltering factory in southern India, Royal Enfield motorcycles are being painted and lacquered by giant robotic arms that move at twice the maximum speed of a human limb, day in, day out, never making a mistake. Only a few workers are still needed on the paint line at Royal Enfield Motors Ltd.’s plant in Oragadam, doing touch-ups on the iconic two-wheelers coveted for their classic design. Four robots…