Norton Commander (motorcycle) Norton Commander (motorcycle) The Commander was a Norton motorcycle with a Wankel rotary engine. The first Norton Wankel motorcycle was the 1987 air-cooled Classic, built as a special edition of just 100 machines. It was followed by the air-cooled Interpol 2 model. The Commander was a liquid-cooled successor to the Interpol 2, liquid cooling being adopted for greater power and reliability. The Commander's final-drive chain was protected by a full enclosure. Some cycle parts (such as front wheel, forks & brakes) were bought-in Yamaha items. Two types of Commander were built. The P52 was a single-seat model equipped for police
Suspension (motorcycle) This USD arrangement has two advantages: (i) it decreases the unsprung weight of the motorcycle; and (ii) it increases torsional stiffness, which can improve handling. Two disadvantages of USD forks are: (i) they are more expensive than conventional telescopic forks; and (ii) they are liable to lose all their damping oil should an oil seal fail. USD forks are typically found on sportbikes, though the Honda Valkyrie featured USD forks. Motorcycle suspensions are designed so that the springs are always under compression, even when fully extended. Pre-load is used to adjust the initial position of the suspension with the weight