Norton Classic

Norton Classic

Manufacturer	Norton Motorcycle Company
Also called	P43
Production	1987
Engine	588 cc air-cooled twin-rotor Wankel engine
Transmission	duplex primary chain, 5-ratio gearbox, single-row final drive chain
Wheelbase	1,486 mm (58.5 in)

The Classic is a motorcycle built in 1987 by Norton as a special edition of just 100 machines.

The Classic used an air-cooled twin-rotor Wankel engine that had been developed by David Garside at BSA.^[1][2] Wankel engines run very hot, so Garside gave this air-cooled motor additional cooling air that was filtered and drawn first through the rotors and then through a large plenum into the combustion chambers via carburreters.^[3] The cool plenum (which doubled as a semi-monocoque spine frame) and the transfer of latent heat during the carburation process significantly reduced the temperature of this fuel-air mixture, but its volumetric efficiency was still somewhat impaired. The cooling air filter was mounted below the steering head (between the forks) to provide a partial ram air effect. The engine was lubricated by oil-injection, but the fuel-air mix also carried a mist of oil from the interior of the rotors, which helped to lubricate the rotor tips.

The fork stanchions were protected by rubber gaiters; and a full enclosure protected the final-drive chain. While its engine was revolutionary, in other respects, such as appearance, suspension and brakes,the Classic was a conventional standard motorcycle. The Classic was lighter and more powerful than its only Wankel competitor, the over-complicated single-rotor Suzuki RE-5 motorcycle.

The Classic was discontinued after a limited production run, and was succeeded by the liquid-cooled Norton Commander. Liquid cooling provided both greater reliability and greater power, at the expense of an arguably less attracive engine (which was concealed by a full fairing).

The Norton Wankel engine was further developed at Staverton into the MidWest aero-engine. The Midwest engine increased output from 85 bhp to nearly 110 bhp^[4] by improving volumetric efficiency, achieved by dumping overboard (rather than burning) the hot rotor cooling air, and by feeding fresh cool air to the combustion chambers.

Notes

1. ^ The Wankel Rotary Engine: A History By John B. Hege page 137, ISBN 978-0786429059
2. ^ Denniss, Tony (1990). "The Norton Rotary". http://www.nortonownersclub.org/history/rotary. Retrieved 14 August 2011. 
3. ^ "Cycle World' magazine February (?) 1971
4. ^ MidWest Engines Ltd AE1100R Rotary Engine Manual

References

Perkins, Kris (1991). Norton Rotaries. The Crowood Press. ISBN 1-826126-062-8. 

Magrath, Derek (1991). Norton the Complete Story. Osprey Publishing. ISBN 1-855532-181-5.