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).
Road test report detailing steering, suspension, and frame issues after extensive testing.
| Identifier | ExFiles\Box 97\5\ scan0012 | |
| Date | 20th January 1939 | |
| -2- RM{William Robotham - Chief Engineer}/APM.9/MH.{M. Huckerby}20.1.39. Steering. The car goes straight on a straight road than any other car known to us - much straighter than the 'M' series Bentley C.B.IV. The steering is admirably light. Such skids as we had we corrected without difficulty. We had a lot of trouble with joggles. These can be due to three causes:- (1) Defective dampers. (2) Frame weakness. (3) Wheels and tyres out of balance. We can say now that dampers affect the steering very little: that out of balance tyres are a serious cause of joggles on straight roads, and that frame front end weakness causes joggles, chiefly on corners. When we left the car the joggles were less serious as the wheels were in balance. Suspension. It is possible to drive the car fast without discomfort under almost any circumstances. For fast touring the control is best in "medium" position on French roads, and in "maximum" is an admirable "harshness" producer for the man who thinks this is synonymous with control. Something more elaborate in the way of front dampers is desirable for further improvement to the ride, to stop floating of the front end without introducing harshness. Cars intended for sale in France should have rather harder front dampers than standard. On arrival in France we found the N.S.F. damper poundage slightly low: the trouble was due to pitting of the replenishing valve seats. The seat and valve are both mild steel at present. We made the seat oil tight. Frame. The 27,000 miles in France has loosened the front end rivets, the result being front end shake and steering joggles. The shake was accentuated by out of balance front tyres. The welding, introduced after C.B.IV. was built, ought to stop this trouble. We think the rivets on production frames will have to be inspected. | ||