chamber by unwanted deposits, which can cause the apex seals to stick. Suzuki opted for a compromise by using two sets of ignition points. One set of points ran on a dual lobe cam for normal operation, firing the rotor every face. The other set ran on a single cam on the same shaft for triggering the spark plug on overrun. The second set (the B points) were triggered by an rpm sensor (the speed relay) and a vacuum switch, which meant that they worked on engine deceleration (high vacuum) and above 1,700 rpm. This system fired the rotor every second face. This kept the combustion chambers relatively clean. It also served to smooth the lumpy feel of the bike as RPM reduced on overrun and addressed some issues with backfiring (more correctly, "afterfiring"). Engine braking is also significantly improved. The B point system was discontinued on the "A". It is believed that the factory also employed mechanics to visit dealerships and disconnect the B points on any "M" (1975) models still in the showrooms. Suzuki toyed with the idea of two plugs like the Mazda's, but as with so much of their engineering on this bike, overthought the application, believing that they would require two plugs of different heat ranges. The idea was dropped, and the bike shipped with a single 18 mm conical seat gold palladium spark plug housed in a copper insert in the rotor housing (NGK A9EFV). Cooling The rotary engine places severe thermal stresses on its cases, as two sides of rotor are constantly exposed to high ignition and exhaust temperatures, while the third side inducts cool fuel/air mixture. To cope with this, and probably capitalizing on their previous experience with water cooling, Suzuki opted for a liquid-cooled engine using two separate systems. Oil is used to lubricate and cool the internals of the rotor and water-cooled the external jacketing. Oil is fed from an engine sump by a trochoid pump at around . The oil is then circulated through an oil cooler mounted across the frame and below the radiator. A pressure regulator also acts as a bypass in case of a blockage in the cooler. A centrifugal pump sends coolant around the external rotor jacketing but via an intricate path in an attempt to even out the massive thermal stresses. Liquid enters at the point of highest temperatures (ignition), passing from the right