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).
Rear spring breakages and suspension damping characteristics, referencing specific models and a complaint from Mr. Rudyard Kipling.
| Identifier | ExFiles\Box 67a\1\ scan0079 | |
| Date | 24th February 1926 | |
| - 2 - BYS/H.{Arthur M. Hanbury - Head Complaints} 24.2.26. ----------------- breakages and then other matters will become less important again. Whilst we have only very occasional breakages of rear springs, we do still get broken springs occasionally, but we must not forget we put into force an instruction to change all thick leaf springs as a result of Mr.Rudyard Kipling breaking two rear springs in fairly rapid succession, and criticising our springing very bitterly in consequence, whilst of course many other people had similar experiences. We find we get in service what we get in France. The 20 HP. particularly suffers from spring breakages in service as it did in France. A spring generally breaks its main plate; occasionally a secondary plate fails, but not often. The frame is then supported by the rubber buffer resting on the axle. It is not dangerous, but it is certainly alarming. Riding such as you require over ordinary roads demands frictionless or undamped spring oscillations, but for faster work these springs are impossible, hence we use shock dampers and springs which are self-damping, i.e. many thin plates. To get what you are now asking for demands a return to the old design of few plates of large dimensions. BJ's complaint re 11-KX was in my opinion due to nothing but shock absorber effects. These would be set up to suit fast driving on bad roads, which resulted in direct transmission of shock from axle to frame member via the shock damper connection, which is of course rigid for its particular "load setting". The rear springs on 10-LW were relatively nearly 300 lbs. stronger than those fitted to 121-HC, yet undoubtedly the former, under the conditions specified, rode lighter and easier due solely to absence of damping. We have reduced 121-HC a further 200 lbs. per spring, and reduced axle clearance to 3.500" only between buffer and axle, a figure we have never dared to risk before. I am of opinion that to get what you require on 121-HC you will have to permit me to order you a set of thick leaf springs. BY.{R.W. Bailey - Chief Engineer} | ||