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).
Published letter to the editor discussing the merits of true pivotal steering, with a diagram and an image of a Rudge-Whitworth wheel.
| Identifier | ExFiles\Box 32\2\ Scan002 | |
| Date | 4th March 1911 | |
| FRONT WHEEL BRAKES AND TRUE PIVOTAL STEERING. [16600.]—With reference to your editorial note at the conclusion of my letter [16554] in The Autocar of February 18th, Mr. Hubert Woods used exaggerated diagrams to illustrate his article in The Autocar of December 3rd last and got exaggerated results. I enclose a diagram showing the effect of the pivot taking a considerable angle to the central plane of the wheel. I have taken Mr. Woods's angle, although this is nearly twice as big as is required. It will be seen that, having regard to the widespread area of the contact of the road and the tyre the effect of this departure of the axis of the steering from the centre of that area will be absolutely negligible in actual practice. There are other causes for the departure of the axis from the centre of this area of contact to which the vertical pivot is equally liable, viz., errors in tyres, rims, wheels, hubs, bearings, and axles. An accumulation of these would be greater than that represented by the difference between the two systems, and if the objection is valid against either system it is valid against both. The increasing prevalence of front wheel brakes would appear to indicate that such is not the case. The inclined steering pivot carries with it many other advantages, and I do not think it will be ruled out by a purely geometrical or drawing board objection. I have no trade prejudice in this matter at all, for we are already marketing a Rudge-Whitworth detachable wheel which can be used with central vertical pivot steering. I enclose a photograph of one of this type. JOHN V.{VIENNA} PUGH. A Rudge-Whitworth detachable wire wheel with a hub specially designed for centre steering pivots. | ||