The Norton Commando 850 Engine: How Isolastic Mounts Tamed Brutal Vibration

The Norton Commando 850 shouldn't have worked. By the early 1970s, Norton was still relying on a long-stroke 360-degree parallel-twin engine whose basic architecture dated back decades. It delivered impressive torque and unforgettable character, but it also produced brutal vibration that threatened to make the motorcycle obsolete. Instead of abandoning the engine and starting from scratch, Norton engineers pursued a completely different idea. They developed the Isolastic mounting system, allowing the engine to move within the frame while isolating much of its vibration from the rider. In this video, we uncover the remarkable engineering behind the Norton Commando 850 and explain how Isolastic mounts transformed one of the biggest weaknesses of British parallel twins into one of the greatest handling motorcycles of its era. We explore why 360-degree twins vibrate so intensely, how the Isolastic system actually worked, the evolution from the Atlas to the Commando 750 and 850, and why riders described the Commando as feeling alive rather than simply smooth. You'll also discover the technical details behind the 828cc engine, including its 77 mm bore, 89 mm stroke, torque-focused design, frame development, and the precise engineering decisions that allowed Norton to compete against motorcycles like the Honda CB750, Triumph Bonneville, and Kawasaki Z1 during one of the most competitive periods in motorcycle history. More than just the story of an engine, this is the story of how brilliant engineers solved an impossible problem without replacing the machine at its heart. It's a fascinating chapter in British motorcycle history that continues to influence engineering thinking decades later.