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).
Letter from the American office to Derby discussing riding quality issues, specifically front axle tramping and shimmy.
| Identifier | ExFiles\Box 43\2\ Scan187 | |
| Date | 2nd December 1926 | |
| ROLLS-ROYCE OF AMERICA, INC. SPRINGFIELD, MASS. X.3900 Oy2-E-12226 December 2nd, 1926. Mr. E.{Mr Elliott - Chief Engineer} W. Hives, Rolls-Royce, Ltd., Derby, England. (Copy for attention of Mr. Haldenby) Dear Mr. Hives: re Riding Quality Was most interested to get your note of November 16th in reply to mine of November 8th describing our troubles with riding on f.w.b. axle. Since writing mine of November 8th we have succeeded in getting what we all consider excellent riding quality on the f.w.b. experimental car, by getting the front springs down to R.{Sir Henry Royce}'s recommended minimum stiffness i.e. 30% of the load. (Load 1100 lbs., stiffness 330 lbs./in. when clamped to the axle.) But we still suffer from the small tramping action of the front axle which shakes the front of the car at all road speeds. Though the R.R.hydraulics are best for controlling this tramping action, even they are not quite prompt enough in their action to cancel it entirely because of its high frequency (about 550 per min). It shows no tendency to break into a "shimmy" but is constantly present and produces annoying squeaks and rattles in the bonnet and body. We have been wondering why you have still been writing of high-speed shimmy, hydraulic dampers on steering gear etc., while with the new, less reversible steering and new f.w.b. axle we get no shimmy but only the tramping action referred to above. | ||