1974 Suzuki RE5 Rotary

Make Model	Suzuki RE5 Rotary
Year	1974
Engine	Liquid/oil cooled, single rotary housing
Capacity	498 cc / 30.4 cu in
Compression Ratio	9.4:1
Induction	Mikuni 18-32 HHD carburetor
Ignition	Dual ignition system
Starting	Electric and kick
Max Power	46 kW / 62 hp @ 6500 rpm
Max Torque	74.5 Nm / 7.6 kgf-m / 55 lb-ft @ 3500 rpm
Transmission	5 Speed
Final Drive	Chain
Front Suspension	Telescopic, oil-dampened forks
Rear Suspension	Swing arm oil dampened, 5-way adjustable
Front Brakes	2 x Discs
Rear Brakes	Drum
Front Tyre	3.25-H19 4PR
Rear Tyre	4.00-H18 4PR
Dimensions	Length: 2220 mm / 87.4 in Width: 870 mm / 34.3 in Height: 1170 mm / 46.1 in
Wheelbase	1500 mm / 59.1 in
Ground Clearance	170 mm / 6.7 in
Dry Weight	230 kg / 507 lbs
Wet Weight	252 kg / 556 lbs
Fuel Capacity	16.8 Litres / 4.4 US gal / 3.7 Imp gal
Consumption Average	7.5 L/100 km / 13.3 km/l / 31.3 US mpg / 37.6 Imp mpg
Standing ¼ Mile	13.9 sec / 150 km/h / 93 mph
Top Speed	176 km/h / 110 mph

Suzuki presented its first, and only, rotary engine powered motorcycle at the Tokyo Show in late 1973. The RE5, as the model was called, was Suzuki's technical flagship at the time and a fine motorcycle. The engine, originated from NSU in Germany, was smooth, quiet, powerful and had hardly any vibrations, thanks to its construction with no parts moving back-and-forth like the usual Otto engine.

The rotary, or Wankel, engine has a number of benefits over standard engines including a lack of camshafts, intake and exhaust valves, and a reduced number of moving parts. Many manufacturers experimented with the engine type and some prototypes were presented in the early 70's but Suzuki was the only motorcycle manufacturer that used the rotary engine on a mass produced bike.

Suzuki presented the engine sometimes as 1000cc, because some regulatory bodies de-rate the engine by doubling the chamber capacity. The actual cylinder capacity was 497 cc.

The design of the RE5 was not as revolutionary as its engine. The instrument panel and tail light were contained in cylindrical shapes to play on the rotary theme, otherwise the bike looked a lot like the company's two-stroke flagship GT750. Also included was a special heat shield since the rotary engine design tended to make exhaust pipes hot enough to burn riders' legs.

What happened? The customers did find the RE5 interesting, but not many but not many of them actually bought the model. Perhaps it was the new technology that scared off the customs, perhaps it was the heavy fuel consumption that made it. However, Suzuki had invested enormous sums of money to the project and had built an entire new assembly line for the rotary engines but the machines wouldn't sell.