From the Rolls-Royce experimental archive: a quarter of a million communications from Rolls-Royce, 1906 to 1960's. Documents from the Sir Henry Royce Memorial Foundation (SHRMF).
From André Dubonnet detailing the characteristics and advantages of the Dubonnet independent suspension system compared to others.
| Identifier | ExFiles\Box 154\1\ scan0145 | |
| Date | 19th May 1934 guessed | |
| ANDRÉ DUBONNET 33, RUE DES GRAVIERS (114, BOULEVARD MAURICE-BARRÈS) NEUILLY TÉL. MAILLOT 19-96 fresh oil for the shock absorber thereby avoiding any variation in the working power of the shock absorber. (6) For jacking up the wheel the same difficulties are encountered in all systems of independent wheels. (7) There is no doubt there is a definite economy in wear on tires in the Dubonnet system as it is the only system existing which never changes track or camber. (8) The ensemble of the Dubonnet system is not heavier than the wishbone system for the same weight of material. HA! HA! It is certain that with a perfect but difficultassemblage and if there were no play in any of the very numerous joints, one could obtain for a certain time in the wishbone system a satisfactory steering but as soon as these joints are a bit worn there are violent kicks in the steering wheel. As these many joints are constantly exposed to dust and mud it is easy to understand that the wear is rapidly noticed. The unquestionable advantages of the Dubonnet system over all other systems of Independent Suspension: (1) The steering being sprung weight all reaction and shimmy are eliminated regardless of wheel action. (2) The wheel always stays in its trajectory without change of track or camber. (3) Complete absence of joints as all articulations are enclosed in a box and are properly oiled at all times. (4) Extreme sensitiveness due to the absence of friction caused by the joints or silent block which exist in all other systems. (5) Presentation much neater--no upkeep as all moving parts are sheltered from dust and mud. (6) Unnecessary to make any modifications to the existing steering. (7) Maximum of sprung weight, minimum of unsprung weight, only the wheel is not suspended. | ||