Suzuki RE5 - History

History

The RE5 was touted as the future of motorcycling. Indeed, RE5 section chief Shigeyasu Kamiya of Suzuki Motor Corporation stated that they had considered a rotary-powered motorcycle as early as the mid-1960s. Basic research and development continued to the end of the decade and culminated in the signing of a technical licence with NSU in November 1970. Suzuki was the 20th firm to do so. The company was at the cutting edge of rotary development and engineered in-house dozens of machines for the rotary production process. Of these, ten were particularly special and included the machine to cut the trochoid block. This one machine alone took a year to reach experimental status. The company also holds twenty patents in plating, as considerable research went into the composite electro-chemical materials (CEM) which were used to plate the rotor housing. Testing of the running prototypes took two years. The bikes were launched in 1974. Suzuki enlisted astronaut Edgar Mitchell, the sixth man to walk on the moon, to introduce the bike and give it his endorsement. No expense was spared, and about a dozen motorcycle publications were treated to a week-long test ride and instructional session on the motorcycle. Journalists were flown around the US west coast in Cessna Citation jets to take their turn riding five pre-production bikes. This corporate attitude extended to the warranty. It was superior to other motorcycles of the day and a full engine replacement stipulated for any engine problem within the first 12 months or 12,000 miles (19,000 km).

Despite having only a single rotor, the RE5 was mechanically complex and was a heavy motorcycle. The rotary engine produced a lot of heat, which required a number of subsystems such as water and oil cooling and modifications to engine components such as the exhaust pipes. Ignition was CDI but used two sets of ignition points through vacuum and rpm sensors to light the one NGK gold palladium spark plug. There were three separate oil tanks (sump, gearbox and total loss tank) and two oil pumps (one for normal engine lubrication and cooling and one to supply oil specifically for tip seal lubrication). The throttle controlled not only the primary carburetor butterfly but a second valve in the inlet manifold of the secondary throat (the "port" valve) as well as the oil pump which provided lubrication for the tip seals by mixing oil with fuel. Five cables in total were moved by the throttle twist grip. The carburetor was similar to that from a rotary power unit in a car and was complicated, by motorcycle standards of the day.

The RE5 could also be optioned with a full touring kit. This included a large full fairing and windscreen, two saddlebags, a large rack and top box. The fairing included two lockable "gloveboxes", and all three bags were also key-locked. Suzuki later made available bolt-on exhaust extensions which prevented damage to the underside of the saddle bags by the hot exhaust gases. An optional touring saddle may have been also available.

Suzuki commissioned Italian industrial designer Giorgetto Giugiaro for the RE5 styling. The "tin can" instrument cluster encompassed the usual lights and a low-fuel warning light, total loss oil tank light and digital gear indicator. This tubular "can" motif was also used in the tail light, and spherical indicator lights finished off the "rotary" theme. The 1976 "A" model returned to more conventional styling. Suzuki expected its sales teams to promote the model alongside the 1977 model GS750, but production had already ceased. The UK-based Rotary Owner's Club records the earliest serial number as 10049 and the highest 16291. From this total production, numbers of something more than 6,000 bikes for both models are indicated.

As of 2010, Suzuki's newly opened museum in Japan does not feature an RE5.